ACCELERATEBreaking the Flat Line

1.1 The line in one chart#Comment

Exhibit 1 shows Christianity’s share of the world’s people from the first century to 2050, Exhibit 2 the numbers behind that line since 1900, and Exhibit 3 net growth by period. Read together, they say one thing: there have been only two sustained rises in share, one in antiquity and one in the nineteenth century, and since about 1910 the line has been flat. There are almost five times as many Christians as in 1900 (0.56 to 2.67 billion), but the world has grown fivefold too, so the share of humanity has stayed within a band of about 32–35% for 125 years ¹.

Two cautions. First, the figures before 1800 are estimates or models, and those between AD 300 and 1800 have not yet been checked against their primary source (Johnson & Chung 2004. The Atlas of Global Christianity) ^{20, 19}. They are shown because the shape matters more than the decimals, and the shape is not in doubt. Second, the modern figures depend on the source: CSGC has Christianity edging up to 34.1% by 2050, Pew’s 2015 projection has it at 31.4%, and holding recent growth rates constant gives 32.6% ^{2, 7}. CSGC’s line rises, but on African births rather than on conversion, the demographic lift the grid in Part 5 takes as its central case. None of the three rises because the church grew faster than the world.

1.2 Engine one: inside out (AD 33–313)#Comment

Rodney Stark’s reconstruction of the early church starts with about 1,000 believers in AD 40 and reaches about 6.3 million, roughly a tenth of the Roman Empire, by AD 300 ⁹. That requires growth of about 40% a decade, about 3.4% a year, in a world whose population was nearly static at 188–209 million ¹². Bart Ehrman’s revision starts from a smaller group, assumes faster growth early that slows to about 34% a decade in the second and third centuries, and reaches about 3 million by 300 ^{10, 11}. Both are models, not counts. Either way it is the highest sustained net growth on record, and it happened before the church could build in the open.

Stark makes a second point that matters for this paper: 40% a decade is not a miracle rate ⁹. The church has seen faster within living memory: the Pentecostal and charismatic movement grew from under a million people in 1900 to 676 million in 2026, about 5% a year sustained for more than a century ¹ (Section 1.7). It is the ordinary pace of a committed movement that spreads through personal networks. Ten believers reaching four people in ten years. The early church did not grow because a few were extraordinary. It grew because almost everyone was involved.

Who carried it. The book of Acts records the pattern. When persecution scattered the Jerusalem church, “those who had been scattered preached the word wherever they went” (Acts 8:1, 4). The church at Antioch, which later sent Paul, and where believers were first called Christians, was planted by unnamed refugees from Cyprus and Cyrene (Acts 11:19–21). Celsus, the movement’s sharpest second-century critic, sneered that its advocates were “wool-workers, cobblers, laundry-workers, and the most illiterate and bucolic yokels” ¹³. He meant it as an insult. It was a description of the engine.

How it was formed. The early church left no treatise on evangelism and no mission strategy. What its leaders wrote about at length was patience: Tertullian, Cyprian and Augustine each wrote a treatise on it. Alan Kreider argues that the church grew through a way of life, a habitus formed slowly in its members and visible to their neighbours, more than through public preaching ⁹⁶. The church order known as the Apostolic Tradition prescribes up to three years of instruction before baptism, with sponsors: existing believers who walked alongside each candidate and vouched for how they lived ⁹⁷. Its date and authorship are contested, so it shows what one tradition prescribed, not what every church practised (Estimated). This reconciles the two things this paper says about the early church. Formation was slow for each believer, and the movement was fast because almost every believer was forming someone: four hundredths of a person per believer per year is a patient rate. The acceleration came from breadth, not from haste.

The words tell the story. The New Testament uses laos (people) and klēros (allotted portion) for the same people: everybody. Only later did the first become “laity” and the second “clergy”. Ekklēsia was the assembly summoned out to decide and to act, never a word for a crowd that watches ²³. And the church’s life had three rooms from the first chapter of its history (Acts 2:42–47): the house, where people found life together. The temple, where they met God. And the market, where they made a difference. All three, day one. This paper returns to those three rooms in Part 6.

1.3 The switch-off (313 onward)#Comment

In 313 the Edict of Milan ended persecution. Within a few years the Empire was regulating who could enter the clergy: a law of 320 barred town councillors and their sons from taking orders, and a law of 326 limited new clergy to replacements for those who died ¹⁴. Ministry had become a career that had to be rationed. Stark’s model has the Empire more than half Christian by 350. That figure is an extrapolation and should not be quoted as fact, but a Christian majority by the late fourth century is plausible ^{9, 10}. Establishment as the official religion followed in 380.

The numbers went up while the engine went off. The believers who had carried the faith through households and workplaces became an audience, and a professional class did the ministry for them. Our teaching series on this period puts it in four words: the church was slowed, diluted, professionalised and deactivated. The building did not deactivate the church. Patronage did ²³. The momentum ran on for two centuries, and the Empire finished becoming Christian under establishment (Exhibit 3 shows about +0.9 a year for 300–500, Unverified). Then it stopped at the Empire’s borders. Net growth after 500 fell to about zero and stayed there for thirteen centuries (Exhibit 3; Unverified before 1800). The mechanism had changed, and the growth that followed neither travelled nor lasted. A caution for today follows: a full room is not evidence that the church is working. Numbers can rise while the engine is off.

1.4 The church that went east and south, and what it lost#Comment

Engine one did not run only inside the Roman Empire, and the first millennium of the church was not a European story. Armenia became the first Christian state in the early fourth century (301 by tradition, 314 on most recent dating), before Constantine. The kingdom of Aksum in Ethiopia followed within a generation. The Thomas Christians of India trace their churches to the first century. And the Church of the East carried the faith along the trade routes to Persia, Central Asia and, by 635, to the Chinese capital ⁸⁴. Philip Jenkins’s reconstruction suggests that by the 780s about a quarter of the world’s Christians looked to the Patriarch of the Church of the East in Baghdad rather than to Rome or Constantinople, and that Africa and Asia together held about a third of all Christians around 1200 ⁸⁴ (Estimated). Then it collapsed: Christians in Asia fell from about 21 million in 1200 to about 3.4 million in 1500, under persecution in China, the Mongol wars, Timur’s campaigns and plague, and Africa and Asia’s share of the world’s Christians fell to about 6% ⁸⁴.

Two things follow for this paper. The map of Christianity has been global before, and it was global when the first engine was running. “from everywhere to everywhere” is a return, not an innovation. And a church that is not handed on to the next generation of its own people can disappear within a few centuries, however far it has spread. The switch-off in 1.3 and the collapse in the East are the same lesson from two directions.

1.5 Renewals that carried the fire#Comment

Across those centuries, the movements that grew re-activated ordinary believers. Four are worth naming, because each one maps onto a layer of the handover model in Part 4.

• Celtic mission (fifth to eighth centuries). George Hunter’s reading of the Celtic pattern is that people were welcomed into the community first and came to faith within it: belonging before believing ¹⁵. Hunter’s account is an interpretation, not a census, but the sequence is the one Part 3 finds still working in Africa. It maps to Belong.
• The Jesuits (from 1540). A movement built on formation and radical obedience, which carried the faith to Asia and the Americas through a small number of deeply formed people. It maps to Depth.
• The Moravians (from 1727). A community of a few hundred refugees at Herrnhut kept a prayer watch for a century and sent out missionaries within five years, under the cry “May the Lamb that was slain receive the reward of His suffering” ¹⁶. Their marks were strategic mission, unceasing prayer, humility, and love for one another. They map to Trust and Lead: ordinary people trusted with the mission.
• The Awakenings (1730s to 1840s). Shut out of the pulpits, George Whitefield preached in the open air to the miners of Kingswood near Bristol in February 1739. He was 24. By April he had handed the crowds to John Wesley and moved on ^{122, 123}. Whitefield gathered people and Wesley kept them. From 1742 every Methodist belonged to a class of about twelve that met weekly under a lay leader, and lay preachers went where the clergy would not ⁷⁸. Wesley saw what happened without it. Where there had been preaching but no societies he judged in 1763 that “nine in ten of the once-awakened are now faster asleep than ever” ¹²³ (Unverified, his own estimate). Finke and Stark’s reconstruction of America shows the result: church adherence rose from about 17% in 1776 to about 37% in 1860, and the Methodists grew from 2.5% of adherents to 34.2% by 1850 ⁷⁷ (Estimated). They map to Belong, Depth and Lead.

The pattern across all four is the same. Each renewal put ordinary believers back to work, and each grew at rates the settled church around it did not. None of them began by building or by professionalising. Several of them ended that way.

1.6 Engine two: outside in (about 1792–1910)#Comment

The second rise in share came from a different engine, and the first engine lit it. In 1748 Jonathan Edwards called for a “visible union of God’s people in extraordinary prayer” ¹²⁵. In 1784 the Baptists of Northamptonshire began to pray monthly on that call and invited other denominations to join them ¹²⁶. William Carey was among them. His Enquiry of 1792 and the Baptist Missionary Society founded the same year opened the Protestant missionary era. The London, Church and American Board societies followed within twenty years ¹⁷. The World Missionary Conference at Edinburgh in 1910 marked its high point ¹⁸. Between 1800 and 1900 Christians grew from about 204 million to 558 million, and the world share rose from about 23% to 34.5%: net growth of about four-tenths of a point a year, the largest gain since antiquity ^{1, 12} (Estimated, the 1800 figure is secondary). Where that gain came from needs saying plainly, because Finding 3 rests on it. It was not, for the most part, conversion on the mission field. In 1900 about 94% of the world’s Christians still lived in Europe, the Americas and Oceania, and only about 32 million, 6%, in Africa and Asia ¹. The century’s increase of about 350 million came mainly from births and migration in the Christian populations of Europe and the Americas, which grew about two and a half times over while the world grew by about two-thirds ¹² (Estimated. The regional split of Christians in 1800 is still to be checked against Johnson & Chung ²⁰). Two things made those births count, and both are the first engine at work. The heartland that grew had just been re-activated: the Awakenings of Section 1.5 raised church adherence in the United States from about 17% to 37% ⁷⁷, and a church that kept its own young people grew with its population instead of losing share to it. And the missions of that century took root where local believers carried them, so that the harvest came in the next one: Africa’s 9.6 million Christians of 1900 became 754 million by 2025, much of it conversion from traditional religion in the first half of the twentieth century, and the rest births in families that had become Christian ² (Section 1.7). The share rose because Christian populations grew faster than the world. That they were Christian populations at all, and stayed so, was the part that was not automatic.

This engine reached the world. It planted the churches that now hold most of the world’s Christians, translated Scripture into hundreds of languages, and built schools and hospitals across Africa and Asia. But its shape was different from the first engine. The faith was sent: from a Christian heartland outward, from a centre to the edges, through missionaries funded from home.

Who carried it where it took root. Not, for the most part, the missionaries. Many of the senders were ordinary believers themselves: Carey was a shoemaker, the Moravians sent artisans, and by the early twentieth century women made up most of the American missionary force ¹⁰¹. On the ground the work passed quickly to local believers. Around 1908 Protestant missions in Africa had about eight African teachers, evangelists and catechists for every Western lay worker, and in Uganda in 1904 Europeans were barely 3% of the mission workforce ⁹⁸ (Counted, from mission returns). Lamin Sanneh traces the same shift to translation: once Scripture was in the vernacular, the faith was in local hands ⁹⁹. Andrew Walls describes it as each people making the faith its own ¹⁰⁰. In Ghana the Methodist church began in 1831 as a Bible band of Fante believers led by William de Graft. The first missionary arrived four years later and died within the year ¹²⁷. The harvest came in the twentieth century, when Africa grew from 9.6 million Christians in 1900 to 754 million in 2025 ², carried by African churches. Engine two worked where it turned into engine one. Where authority, money and ministry stayed with the mission, it reached people without activating them. And when the sending heartland began to lose its own young people in the twentieth century, the share stopped rising.

1.7 The Pentecostal century: engine one in modern form#Comment

The first engine did not stay in antiquity. In April 1906 a prayer meeting led by William Seymour, the son of former slaves, at 312 Azusa Street in Los Angeles became the launch point of the global Pentecostal movement ⁸⁰. The Welsh revival of 1904–05 had just added an estimated 100,000 converts in a year ⁷⁹ (Estimated). The Pyongyang revival of 1907 shaped Korean Protestantism. And from 1929 the East African Revival spread from Rwanda through Uganda, Kenya and Tanzania, led by lay “saved ones” practising public confession and reconciliation across ethnic lines ⁸¹. Pentecostals and charismatics, under a million in 1900, numbered 676 million in 2026, about a quarter of all Christians, and they are the fastest-growing part of the church ¹. Lausanne’s summary is precise about the mechanism: they are “the leading edge of Christian growth around the world … typically more missionary in orientation, placing a high emphasis on lay evangelism through personal networks” ⁴³ (SGC p. 30).

That is engine one in modern form. The movement hands leadership to ordinary believers immediately. It expects every believer to minister (Joel’s promise of the Spirit “on all people”, Acts 2:17, is its founding text). It grows through households and networks rather than institutions. And in Africa, Latin America and Asia it raised indigenous leaders from the start rather than sending a professional class from a heartland. Part 3 shows where it is now: the churches Ghana’s young are choosing are Pentecostal and charismatic (32.5% of 15–39-year-olds against 28.4% of those 40 and over ³⁷). The 20th century also produced the largest lay-led church growth since antiquity in China, where the numbers are contested but the mechanism, unregistered house churches, is not ⁸³.

Then why did the world line stay flat while this engine ran? Three reasons, and each one matters for what follows. Much of the growth was transfer within Christianity. In Latin America a large share of Protestants were raised Catholic ⁸². In Ghana the young moved from mission churches to Pentecostal ones (Part 3). Activation re-formed existing Christians more than it added new ones. Where it did convert, it was regional. Africa went from 9.6 million Christians in 1900 to 754 million in 2025, much of it conversion from traditional religion in the first half of the century ². But the world line is an average, and Europe and North America were switching off at the same time. And where a revival was not handed on, it faded within a century. Korea’s 1907 revival produced one of Asia’s largest churches. In Pew’s 106 countries South Korea now has the third-largest gap between young and old in religious affiliation, 24 points ²⁸. Activation is not inherited. It has to be done again in every generation, which is the argument of Part 2.

1.8 The church is now everywhere#Comment

The map has changed since Edinburgh. About two-thirds of the world’s Christians now live in Africa, Asia, Latin America and Oceania, and Africa alone supplies about 80% of the growth CSGC projects to 2050 ^{2, 3}. The old picture of a sending centre and a receiving edge no longer describes anything. This section sets out the map as it is: by continent, by the regions NXT Move works in, and by the 10/40 Window, where the line has to bend.

Exhibit 7 shows why the world line stayed flat while the map changed. Each column is a continent, as wide as its share of the world’s people and filled to the share that is Christian. Between 1900 and 2050 the two columns that were almost wholly Christian, Europe and Northern America, narrow from 30% of the world to 12%, while Africa widens from 7% to 26% and fills from 9% to 52%. Asia is the constant. It holds 59% of the world’s people in 2025 and 16% of its Christians, and 79% of everyone who is not Christian lives there, a figure on which CSGC and Pew agree ^{2, 3, 45, 119}. The line will not bend without Asia.

Three maps. The paper reads the world through three maps, and Exhibit 8 sets them side by side. The long series uses the six UN continents, because only that division has counted data from 1900 to 2050. NXT Move works in eleven regions, drawn from Lausanne’s twelve. The 10/40 Window cuts across both. Asia in the long series is four NXT Move regions, Central, South, East and Southeast Asia, together with most of the Middle East. Africa in the long series is NXT Move’s Africa region together with North Africa. The Window takes in the whole of the Middle East and North Africa, South Asia and Central Asia, all of East Asia except South Korea, most of Southeast Asia and 43% of the people in NXT Move’s Africa region, among them Nigeria and Ethiopia. Two in three of the world’s people live inside it, and nearly nine in ten of those who are not Christian ^{119, 120, 121}.

Where the weight falls. The flat line is a world average, and this paper reads it as one. Every region appears in it twice: as a teacher and as a learner. Europe and North America show the end of the decline sequence and the first counted signs of return. Latin America shows how fast the South can slide within a generation. Asia holds both the largest lay-led growth of the last century and the largest unreached populations. The Middle East shows resilience under pressure. Africa shows the beginning of the sequence, with belonging intact and trust under strain. The weight is not equal, and the paper does not pretend it is. Africa supplies about 80% of the Christian growth projected to 2050 ², so it carries the most weight in the grid of Part 5 and receives its own Part 3. But the four conditions of the handover in Part 4 are the same on every continent, the regional evidence is set side by side in Section 2.8, and the strategy in Part 6 is written for everywhere to everywhere. One asymmetry runs the other way. Africa carries the weight of retention. Asia carries the weight of multiplication, because nearly four in five of the world’s non-Christians live there (Section 5.7).

The leaders of the 10/40 Window, the region with the most unreached young people, say the same thing from the other side. When NXT Move convened twenty-plus of them in September 2026, their guiding conviction was that God has already raised leaders across the Window, and that the task is to bring them “from isolation into kingdom collaboration so the next generation reaches the next generation among the least reached” ²⁶. One of the collective’s five goals is sending from within the Window. Filipino leaders said their country now needs to step up as a sending nation to its neighbours. Leaders in Central Asia and the Middle East asked for young believers to be equipped to stay and reach their own societies. Diaspora communities were named as a lever ²⁶. The initiative’s own summary: “The world’s most unreached young people are not waiting for a better strategy. They are waiting to be activated” ²⁷.

The phrase for this is not new. Michael Nazir-Ali named it in 1990: mission from everywhere to everywhere ²¹, and the Cape Town Commitment made it the working assumption of the global evangelical movement ²². What this paper adds is the arithmetic. Neither engine on its own will bend the line now. Outside-in mission cannot, because there is no longer a heartland with the people or the money to send at the scale needed, and because the last century shows that reach without activation goes flat. Inside-out activation in one region cannot, because the flat line is a world average. The next surge requires both at once: every church activated, and every church sending.

1.9 Reactivation at scale: the 2033 horizon#Comment

That is the reasoning behind the work NXT Move serves as backbone organisation. The Next Gen Global Collab brings together more than thirty organisations from more than twenty nations around one goal: that everyone in the next generation has an opportunity to follow Jesus by 2033, roughly two thousand years after Pentecost ⁶⁰. Through 2026 the same horizon has drawn other leaders into collaboration conversations about mobilising believers toward evangelism, from every believer as a witness to the season between Easter and Pentecost ²⁴. What follows is the thinking those conversations have produced, not an organisation chart.

Three convictions from them run through the rest of this paper ²⁴:

• “Duplication is the enemy.” Fragmented effort costs time, and Part 5 shows that time is measured in people: about two million in Africa alone, five million worldwide, for every year the shared response starts later.
• Activation is the superpower. Not training, not events: mobilising the believers who are already there. This is engine one, restarted.
• Coming together only matters if it leads to acting together. The prayer of John 17 is “that they may be one … so that the world may believe.” Unity is instrumental as well as good in itself. Part 3 shows that displayed unity is also what the next generation’s trust depends on.

The same conversations read the generations plainly: Millennials in the West are largely post-Christian. Generation Z may be pre-revival, “islands in oceans” ²⁴. The islands are real and counted, and the ocean has not yet changed. Section 2.7 weighs that evidence label by label. The teaching series that grew out of this thinking ends with a single challenge for every believer, 1 : 1 : 1: walk with one person (house), invite one person (temple), reach one person (market) ²³. Four hundredths of a person per believer per year built the early church. One-one-one asks far more of each believer than that, and asks it of every believer.

2.1 The age gap#Comment

Pew Research Center pooled surveys from 106 countries taken between 2008 and 2017 and compared adults under 40 with those 40 and over. In 41 countries the younger group is significantly less likely to have any religious affiliation. In only two, Ghana and Chad, is it more likely. The average gap across all 106 countries is about 5 points. It is 28 points in Canada, 26 in Denmark, 24 in South Korea and 17 in the United States ^{28, 29}. The countries whose churches sent the most missionaries in the second engine now show the steepest generational drop-off. Sub-Saharan Africa is different: in 17 of 21 countries there is no significant age difference in how important religion is ²⁸.

2.2 How faith drains: participation, importance, belonging#Comment

Religious decline does not happen all at once, and it does not begin with people leaving. Research across many countries, summarised by Pew in 2025, finds a consistent three-stage sequence: participation falls first (people attend less), then importance (religion matters less to them), and only then belonging (they stop identifying with a religion) ³⁰. Affiliation is the last thing to go. That has two consequences for everything that follows. First, headline affiliation figures lag reality by a generation: a country can be 95% affiliated and already well into decline. Second, the early warnings are in participation and in what young people say matters to them, and those are the layers to watch.

2.3 Switching#Comment

Pew’s 2025 accounting of religious change between 2010 and 2020 finds that for every 100 adults raised Christian, 17.1 have left and 5.5 have joined: about 3.1 leaving for each one joining. The data cover 117 countries and are lifetime measures (childhood religion against current religion), not annual flows ⁵. Christians still grew by 122 million over the decade, so the growth came from births ⁴. Pew’s 2015 projection puts the effect of switching on the world share at about one point by 2050 (31% with it, 32% without) but far more in the North: North America 66% Christian with switching against 75% without. Europe 65% against nearly 70% ⁸.

Two patterns in the country data matter for the rest of the paper. Switching rises with development. In the 51 places Pew classes as very high on the Human Development Index, a median 18% of adults under 55 have left their childhood religion. In the 16 low-development countries, 3% ³¹. As Africa develops, retention will get harder, not easier. The pattern in Africa is not uniform. Nigeria, Ghana and Kenya show almost no net loss. South Africa has already lost about one in nine of those raised Christian. The United States and Chile have lost about one in four ⁶. Part 5 turns these three observed patterns into the rows of the scenario grid.

2.4 What defines this generation#Comment

Hitting the Ball You Cannot See argues that the next generation is being shaped by six shifts, and that churches suffer a “relevance deficit” because technology changes exponentially while organisations change logarithmically ³² (Ch. 2). The shifts are restated below with the evidence in this paper that bears on each. The point of the table is not that the book is right about everything. It is that the global data and the book’s diagnosis converge on the same layer of the problem.

Underneath the shifts the book places four questions, drawn from Barna Group research introduced to the author by Mark Matlock, that every generation asks and this one asks with unusual force: Who am I? (identity), With whom do I belong? (belonging), What truly matters? (values) and What is true? (epistemology) ³² (Ch. 5, pp. 75–76). Part 4 maps them onto the four layers of the handover. What the book adds is the observation that trust runs underneath all four: without it the questions curdle into “I don’t trust who I am”, “I don’t trust the places where I belong”, “I don’t trust that what is valued is valuable” and “I don’t trust what I believe”.

2.5 Trust as the hinge#Comment

The book’s central diagnosis comes from Luke Greenwood of Steiger, who works among Europe’s post-Christian youth: young people “aren’t walking away from truth, but from trust … They’re not saying truth isn’t real. They’re saying, ‘I just don’t trust you to tell me what it is.’” In the United States deconstruction is common. In Europe, “generations never even entered a church—they’re not deconstructing. They never built” ³² (Ch. 5, p. 77).

The wider trust environment is the context. Gallup’s confidence in the church or organised religion has fallen from about two-thirds of Americans in the mid-1970s to 31% in 2026, and it is one institution among many: the medical system stands at 28%, newspapers at 16% and Congress at 7% ^{68, 33}. The church is not exempt from a general collapse of institutional trust. It is one more institution asking to be believed.

The sociologist Josh Packard, whose Future of Faith Institute holds one of the largest bodies of research on religion and young people in the United States ⁶⁷, draws the conclusion this paper builds on: we are living in a trust story, not a belief story, and trust has not disappeared, it has relocated from institutions to relationships ⁶⁵. His institute’s Sacred Listening Study (884 adults and 1,138 teenagers, fall 2024) puts numbers on the relocation. 76% of teenagers and more than 70% of adults report high trust in people they know personally, against 16–26% for institutions and authority figures. 67% of teenagers and 66% of adults say their faith deepens when someone listens to them without judgment. 33% and 34% say the same of sermons. Nearly half of teenagers say they withdraw from communities where they feel dismissed ^{64, 66} (Counted; U.S. panel sample).

Packard’s summary of the practical consequence is the one this paper adopts in Part 6. The old ministry sequence was Truth → Trust → Time: broadcast the truth, expect trust to follow, and then engagement. In a low-trust world it has inverted to Time → Trust → Truth: spend time with young people where they are, earn relational trust, and only then earn the opportunity to share and live out the truth ⁶⁵. Belonging precedes believing. That is what the Celts practised (Part 1), what Africa still shows (Part 3), and what the book means by “establish trust before presenting truth”.

What makes trust the hinge rather than one factor among many is the decline sequence in 2.2. Participation and importance fall before belonging, and both are expressions of trust: whether a young person shows up, and whether what happens there is believed to matter. Three bodies of evidence from three continents now point at the same layer: Greenwood’s witnesses in Europe, Packard’s data in the United States, and Afrobarometer’s trust gap in Africa, where belonging is intact and trust is where the strain first shows.

Trust also runs the other way: it is something young people are given, not only something they give. In Lifeway Research’s survey of 2,002 Americans aged 23–30 who had attended church regularly as teenagers, those who stayed through their early twenties were more likely than those who dropped out to have had regular responsibilities at church as teenagers (56% against 42%) and to have held a leadership position there (39% against 30%) ⁸⁶ (Counted; U.S.; correlational). The survey cannot say which way the arrow runs: committed teenagers may simply be given more to do. But it points to the same place as the trust items in Section 4.3. Being asked to carry something is how a young person learns that they are trusted, and it is where retention and activation meet. Section 6.6 follows that link to church planting.

2.6 The Western warning#Comment

The West is the case where the sequence has run to its end. Davis and Graham estimate that about 40 million American adults have stopped attending church in the last twenty-five years, the largest and fastest religious shift in the country’s history ³⁵. The Pinetops Foundation projected that between 35 and 42 million young Americans raised in Christian families could leave the church by 2050 ³⁴. In Europe the losses are already counted: of adults raised Christian, 36 of every 87 in Spain have left, 30 of 70 in Sweden, 30 of 64 in the Netherlands, 30 of 78 in Germany and 29 of 69 in Britain ⁶. Europe’s Christian share fell from about 95% to about 74% between 1900 and 2025, and Northern America’s from about 97% to about 70% ^{3, 45}.

The warning is not that the same thing must happen everywhere. It is that it happened in the regions that hold most of the church’s money and training, and that it began, in every case, with participation and trust, not with belief. The next generation in the Global South is not immune. It is earlier in the sequence, and (Part 3) in a stronger position to change the ending.

2.7 Islands in oceans: reading the revival signals#Comment

Since 2025 there have been widely reported signs of a revival among young people in the West. A paper that argues the next generation is the hinge cannot be blind to them, and it cannot repeat them uncritically. Read with the same evidence labels as everything else, they sort into three groups.

1. Counted, and real.In France, more than 20,000 adults and adolescents (about 13,200 adults and 8,200 adolescents) were baptised at Easter 2026, 20% more than in 2025, which was itself a record. The largest group of new catechumens is aged 18–25, most had no religious background, and the bishops’ report attributes their journeys to difficult life experiences, a search for meaning or spiritual encounters rather than family tradition ⁷⁰. In the United States, Barna finds 66% of adults say they have made a personal commitment to Jesus that is still important today, up from 54% in 2021, the lowest point in three decades of tracking. The rise is led by younger adults, with Gen Z men up 15 points and Millennial men up 19 since 2019 ⁶⁹. Barna also reports Gen Z and Millennial churchgoers attending more weekends a month than older generations ⁶⁶.
2. Reported, then withdrawn.The Bible Society’s The Quiet Revival (April 2025) reported that monthly church attendance in England and Wales had risen from 8% in 2018 to 12% in 2024, and among 18–24-year-olds from 4% to 16% ⁷¹. In March 2026 the Society withdrew the report after YouGov found that quality controls had not been applied to the 2024 sample, which included respondents outside England and Wales, duplicates and inattentive respondents. No corrected figures have been published, and a new study is due in autumn 2026 ^{72, 73}. Random-sample surveys show no such rise: the Labour Force Survey has 28% of 18–34-year-olds identifying as Christian in summer 2025, down from 37% in early 2018, and the British Social Attitudes survey has monthly-attending Christians among 18–34s at 6% in 2024 against 8% in 2018 ⁷⁴.
3. Counted, and flat.Pew’s December 2025 review finds “no clear evidence of a religious revival among young adults” in the United States: religious composition, prayer, importance and attendance have held steady since 2020. 18–24-year-olds remain far less religious than their elders (30% pray daily against 59% of the oldest adults. 26% attend monthly against 43%). The narrowing gap between young men and women reflects declining religiousness among young women rather than a rise among men. And among young adults 26% have left Christianity while 5% have joined ⁷⁵. The American Time Use Survey shows no increase in young adults’ attendance between 2021 and 2024 ⁶⁶.

How to read the three together. The decline sequence in 2.2 runs participation → importance → belonging. A revival would run the other way, and it would show first in the leading layers (commitment, catechumens, Bible reading, participation among those already reached) long before it showed in population-level affiliation or attendance. That is exactly the pattern in the evidence: the leading indicators are moving in France and in Barna’s commitment measure. The lagging indicators are flat. It is what “pre-revival” and “islands in oceans” mean in Part 1: real islands, an ocean that has not yet changed ⁷⁶. Packard’s warning applies to both: “The Gen Z revival being debated won’t happen in churches that talk but don’t listen” ⁶⁶. And the British episode is a lesson in posture. A movement that asks to be believed must hold its own evidence to the standard it asks of others, which is why every figure in this paper carries a label.

2.8 The hinge around the world#Comment

The same sequence is running on every continent, at different stages. Exhibit 14 sets the regions side by side on the measures this paper uses: the long trend in share, the counted retention of the people raised Christian, where each region sits in the participation → importance → belonging sequence, and what it has to teach the others. Every region is a teacher and a learner in this table. None is only a warning and none is only a hope.

Exhibit 15 reduces the long trend in the table to three points for each continent. Since 1900 Africa has gained 40 points and Asia 6. Northern America has lost 27, Europe about 21 and Oceania 12, and Latin America has held above 90% while its switching data show the slide beneath it ^{2, 3, 45, 6}. The continents that have lost most are the ones where the sequence has run furthest.

Read down the table and the paper’s thesis is regional as well as historical. Where the church has relied on institutions it once trusted, the young have left. Where it has relied on relationships and lay networks (Africa’s churches, Pentecostal movements in Latin America and Asia, the Philippines), they have stayed or joined. And where a revival was not handed on, it faded. Read across, and the four conditions of Part 4 are the same everywhere. Only the stage differs.

3.1 The scale#Comment

Africa accounts for about 80% of the Christian growth CSGC projects between 2025 and 2050: 535 of 667 million. The rest of the world grows by about 7% ². The United Nations’ medium projection puts Africa’s population at 2.47 billion in 2050, and 40.4% of it will be aged 18–43, the cohorts that reach adulthood between now and then ^{45, 46}. Sub-Saharan fertility was 4.3 children per woman in 2024, and Africa’s share of the world’s births is projected to rise from about 36% to about 42% by 2050 ^{48, 49}. Whatever happens to the next generation in Africa happens to the flat line.

3.2 The finding, sized honestly#Comment

Pew’s exception is real but small. Younger adults are 3 points more likely to be affiliated in both countries: 100% against 97% in Ghana and 97% against 94% in Chad, from surveys taken around 2008–09 ^{28, 36}. Both figures sit near 100%, so the gap says more about who isn’t affiliated (a shrinking group of older traditional believers and non-religious people) than about youth enthusiasm. There is also a real, if modest, gain in devotion: young Ghanaians are more likely than their elders to say religion is very important (91% against 85%), and young Chadians are more likely to pray daily (84% against 79%) ²⁹. Pew’s own explanation is insecurity: the countries where the young are more religious “all have something in common: a recent history of violent conflicts” ²⁹. That is a correlation, not a demonstrated cause.

3.3 Ghana, counted#Comment

To test the finding we pulled Ghana’s 2010 and 2021 census tables of religion by age directly from the Ghana Statistical Service’s data service ^{37, 38}. They settle the question for Ghana. In 2021, 5.2% of Ghanaians aged 40 and over were traditionalists, against 2.6% of those aged 15–39. 6.0% of the older group had no religion, against 4.8% of the younger. In 15 of 16 regions the young are less likely to have no religion. In Upper East, 33.9% of over-40s are traditionalists against 15.2% of the young. Older adults were the last to be raised in traditional religion or none. The young grew up Christian or Muslim. Most of the “exception” is one generation replacing another.

Two further findings are more useful than the headline. There is no sign yet of young Ghanaians leaving religion. Comparing the same ages across the two censuses, the share with no religion fell or held steady between 2010 and 2021: for ages 15–19 from 4.3% to 3.6%, for 30–34 from 6.1% to 5.3%, for 35–39 from 6.6% to 5.5%. Nationally it was 5.3% in 2010 and 4.5% in 2021 ^{37, 38}. And the young are moving within Christianity, toward churches that engage them. 32.5% of 15–39-year-olds are Pentecostal or charismatic against 28.4% of those 40 and over. Mainline Protestants are 17.0% of the young against 20.0% of the old ³⁷. Across the censuses, the Pentecostal/charismatic share rose from 24.1% (2000) to 31.6% (2021) while Catholics fell from 15.1% to 10.0% ³⁹. Researchers describe young people migrating from mission churches to Pentecostal and charismatic ones ⁵².

3.4 Chad, counted as far as the data allow#Comment

Chad has no census by religion and age we could access. What the surveys show is the same replacement pattern: traditional religion fell from 7.3% of the population in the 1993 census to 0.3% in the 2014–15 Demographic and Health Survey ⁴⁰ (secondary. The DHS microdata are the next check, and registration for them is in hand). A survey of 1,857 Chadians found the most intense religiosity among those with Arabic or Qur’anic schooling, and Pentecostal churches are growing ⁵³. Chad today hosts more than 1.5 million refugees, and about half its people need humanitarian assistance ⁵⁴. The insecurity Pew points to is not hypothetical there.

3.5 Four explanations, tested#Comment

The combined picture: mostly E1, with some E2, likely driven by E3 in Ghana and possibly E4 in Chad. None of it is a youth revival of the kind that would make Ghana a template to copy. Two things are transferable. Where churches adapt, the young move to churches that engage them rather than leave the faith. And where life is uncertain, faith that meets real need holds the young.

3.6 The wider African picture: belonging holds. Trust and depth are thinner#Comment

Ghana and Chad are the far end of an African norm, not outliers against it. Kenya’s 2019 census recorded 1.6% with no religion ⁵⁰. In Nigeria, Ghana and Kenya, 96–98% of those raised Christian are still Christian ⁶. Across 34 African countries, 95% of people say they have a religion ⁴¹. The strain shows in the layers underneath. Trust in religious leaders is 66% among 18–25-year-olds against 74% among those 65 and over ⁴¹. In OneHope’s online survey of teenagers in Kenya, Nigeria and South Africa, only 28% met the marks of committed Christian faith ⁴² (the sample is urban and connected, and it is unclear whether the base is all teens or Christian teens).

Kenya is the warning. In the 2024 Finance Bill protests, Gen Z Kenyans confronted clergy who hosted politicians and took their donations. Many kept faith in God but lost faith in church leadership ⁵¹. That is exactly the layer where the Afrobarometer gap appears. In Africa, disaffiliation, if it comes, is likely to begin as a loss of trust in leaders, not a loss of belief. And it will come under pressure from development: unemployment in Ghana was 13.6% in 2024, and nearly two million young Ghanaians, 19.5% of 15–35-year-olds, are not in education, work or training ⁵⁵.

What Nairobi is saying back. The warning is being answered from inside the city. Through 2025 and 2026 NXT Move’s Africa team has convened bishops, young leaders and marketplace leaders in Nairobi at one set of tables, and in 2026 those conversations produced a plan for what they call a Missional Garage: church-based spaces where young adults aged 18 to 35 connect faith to work, talent and daily life, using buildings churches already own and supplying the programming and the community, owned by no single organisation ¹³². Beside it sits an incubator that takes a stake in the ventures young people start and asks them to give service hours and training back, so that the work is resourced from inside its own economy rather than from outside ¹³¹. One sentence from those conversations has become the way Nairobi’s leaders now talk about the decade: if a country is seventy percent young and its churches are seventy percent adult, those churches are dying successfully ¹³¹. None of this is counted evidence yet. It is the ‘softens’ row being contested in one city, and the baseline JFINDX takes there in 2026–27 is where it becomes measurable (Section 6.7).

3.7 What travels, and where the money is#Comment

One more fact frames everything in Part 6. North America and Europe together hold about three-quarters of the world’s church income, while Africa holds about 28% of the world’s Christians and about 3.5% of the income. Theological institutions follow the same pattern ^{44, 43}. Lausanne’s summary: “an abundance of investment in a declining Christianity and a growing Christianity institutionally hamstrung by minimal resources.” That is the first gap: between where the next generation’s Christians are and where the resources and training sit. It is the most direct lever in reach.

There is a second gap, and it is larger. The first compares money with Christians. The second compares money and workers with the people who have not heard. About 2.2 billion people, 27% of the world, live without realistic access to the gospel, and CSGC projects the number to rise to 2.8 billion by 2050, because the places where the church is smallest are where population is still growing ² (Estimated; Projected). Fewer than one non-Christian in five personally knows a Christian ². Of about 450,000 cross-cultural workers, Lausanne counts about 15,000 serving among unreached peoples ⁴³ (Estimated). The share of Christian giving that reaches them is widely quoted as about 1% of mission giving, or a dollar or two in every $100,000 of Christian income. Those ratios go back to 2001 ¹⁰⁹, and CSGC no longer publishes the series behind them ², so this paper treats them as Unverified and dated. The direction is not in doubt. The precise size is.

The two gaps call for different responses, and the paper argues for both. Closing the first moves resources and training toward young African leaders (Part 6). Closing the second is not a return to outside-in sending. Most of the church’s workforce is already local: CSGC counts about 13.6 million national workers against 450,000 foreign missionaries ². The need is to sustain the believers and multipliers already inside the least-reached regions, and the senders from Africa, Asia and Latin America who go to them (Section 6.5). How money is given matters as much as how much. The literature on mission funding records how patronage creates dependency and silences local leaders ^{111, 112}, and also warns against demanding a self-sufficiency no one else is asked for ¹¹³. It is the lesson of 313 again: the building did not deactivate the church. Patronage did.

3.8 The rest of the South: an exception, and a warning#Comment

Africa is the largest case of the young holding on, not the only one, and the South also contains the clearest warning. The Philippines keeps almost everyone it raises (95 of every 100 adults raised Christian are still Christian) ⁶, and its leaders came out of the 10/40 Window sessions in September 2026 describing the country as a sending nation to its neighbours rather than a mission field ²⁶. Singapore shows that net gain by conversion is possible in a developed, plural society: 12 of every 100 adults were raised Christian and 18 are Christian now ⁶. Latin America is the warning. A region that was almost entirely Catholic a century ago now shows Brazil at 90 → 76, Mexico at 93 → 78 and Chile at 89 → 66 ⁶. In Brazil’s 2022 census 9.3% reported no religion, and Uruguay was already 37% unaffiliated in 2014 ^{85, 82}. Much of the movement has been within Christianity, from Catholic to Pentecostal churches, and it kept people in the faith for a generation. It did not, by itself, keep the next one. That is the lesson Ghana should read most carefully: adaptation buys time, and the time has to be used to build trust and depth.

4.1 The model#Comment

The evidence in Parts 2 and 3 sorts into four layers. Each is a question a young person could answer about their own faith community, and each can be measured.

Why trust is the foundation rather than one layer among four: the decline sequence puts participation and importance before belonging, and both are expressions of trust. In Africa, belonging is intact and trust is where the strain shows first. In the West, the book’s witnesses say the same thing from the far end of the sequence. A model that treated the four as equal would miss the order in which they fail.

The layers are not stages served by time. A young person moves from one layer to the next when something observable changes, not when enough months have passed. The early church admitted candidates to baptism when their sponsors could vouch for how they lived, not when a course was over ⁹⁷. The Methodist class asked each member every week how it was with their soul ⁷⁸. Two layers carry the link to multiplication. Depth is formed in practices: prayer, Scripture, worship, community, serving, giving and sharing faith, the seven practices NXT Move uses with new believers ¹⁰⁷. Lead shows when a young person walks with someone else in those practices, the house room of 1 : 1 : 1 (Section 6.5). A handover that stops at depth produces retention. One that reaches lead produces multiplication.

The model also reads the book and the history. Each of the book’s four questions (with whom do I belong, what is true, what truly matters, who am I) sits under one layer, and the book argues that trust runs under all four ³². Each renewal in Section 1.5 was strong in particular layers, and the switch-off after 313 can be described as one layer, lead, being removed. The book’s six skills are the leader’s side of the handover. The three crosswalks are set out in Appendix A.7 (Tables A7 to A9). Where the research sharpens the book: the book is written largely from inside the West’s decline (“islands of revival in a sea of decline”). The global data show decline arriving in a different order in the Global South, with trust eroding while belonging holds. That is why this paper presents Africa as the place where the handover can still be secured, and the West as the cautionary case, rather than the other way round.

4.2 Crosswalk to JFINDX#Comment

The Collab already has a shared instrument. The Jesus Following Index (JFINDX) uses the J12 model: three questions (do they follow Jesus, do they join His mission, does their world look different) across four tiers (Exposure, Response, Formation, Multiplication). Member organisations run a seven-minute survey with 13–30-year-olds under their own names, and the results are pooled. A country appears on the map once it reaches 2,000 responses ^{61, 62}.

4.3 The Belong–Trust module#Comment

Rather than build a new index, we propose a short module inside JFINDX covering the two layers the J12 does not yet measure directly. Draft items, for co-design with the NXT Move Africa team and young co-researchers:

• Belong. Do you identify with a religion, and which? Is it the one you were raised in? Is there a faith community you take part in at least monthly? Are there adults there, outside your family, who know you by name?
• Trust. How much do you trust the leaders of your faith community? Is there someone there who listens to you without judgment? When you speak there, do you feel heard? Do you have a real say in any decision? Has a leader ever asked you to lead something? (The listening items are drafted from the Sacred Listening Study so that results can be set beside the U.S. ones ⁶⁴, and will be reworded with the Nairobi co-researchers before the baseline.)
• Context, for the planting comparison (two items). How old and how large is your faith community (under 3 years, 3–10, over 10. Under 50 people, 50–199, 200 or more)? Before you joined it were you part of another church, of none, or did you help start it?

Reported by age group (13–17, 18–24, 25–30) and by city, the module would show whether trust erodes before belonging, the early warning Part 3 points to. It would be run first with the Nairobi table as a baseline, then in Accra and Kumasi, and remotely with Chadian partners. Three standards apply. Pre-specification: the items and the planned age comparisons are published before the 2026–27 baseline. Sampling honesty: JFINDX reaches young people through participating organisations, not random samples, so results are reported as “among those reached” and calibrated against representative sources (Afrobarometer, DHS, censuses), with a school- or household-based random sample in one or two pilot countries. Ethics: parental consent or an equivalent for 13–17-year-olds, data protection, and ethics review through a partner university.

The context items let the module test the planting argument in Section 6.6 without confusing two things that usually travel together. New communities are also small ones, and small settings generate roles. The pre-registered comparison therefore separates the age of a community from its size, and asks one question: does holding a role, or having started something, go with staying, after allowing for community size, tradition and parents’ faith? The prior-church item separates transfer from reach. Where members allow a follow-up a year later, retention is measured by what young people did rather than what they expect to do.

5.1 How the model works#Comment

The model is deliberately simple, so that every number can be traced. It was built for Africa first, because that is where most of the projected growth and most of the variance in 2050 lie (Section 3.1). We combined the United Nations’ three fertility paths for Africa with three retention patterns observed today, and computed Christianity’s share of the world in 2050 for each of the nine combinations, holding the rest of the world at CSGC’s projection. Then we applied the same three retention patterns to every continent, each with its own age structure in 2050, at the UN’s medium fertility. The parameters and their sources are in Table A3, and the arithmetic in Appendix A.3.

Christians in 2050 = rest-of-world Christians + (Africa’s population × Africa’s Christian share × retention adjustment)
Retention adjustment = 1 + (net lifetime switching loss × share of Africa’s 2050 population aged 18–43)

5.2 The regional grid: which lever moves 2050#Comment

The grid applies the Africa model of Section 5.1 to every continent, with the same three retention levels and each continent’s own age structure in 2050, so that the retain and together findings carry global numbers rather than African ones. Everything in it is Modelled, and the inputs and outputs are published (Appendix B.9).

Across the six continents, the difference between the cohorts reaching adulthood before 2050 keeping their faith and following the sharpest observed losses is about 280 million people, 2.9 points of the world’s population (Exhibit 28). Africa carries 120 million of it, Latin America 50 million, Asia 50 million, Europe 30 million and Northern America 20 million. Set against the 0.7 points that the pace of African fertility decline moves the result (Exhibit 30), retention moves the 2050 share about four times as much as births, and about twice as much within Africa alone (Section 5.3). That is the arithmetic behind the thesis: retention decides the level. One caution on the North: CSGC’s 2050 projection for Europe and Northern America already contains a decline (74% to 67%, 70% to 60%), so the ‘erodes’ row there stacks a further loss on a baseline that holds one, and the North’s share of the swing is an upper bound. Asia is the largest uncertainty the other way: whether China’s Christians number nearer 30 million or nearer 100 million adds or removes about one point of world share by itself ⁸³.

5.3 Africa, the test case#Comment

Africa carries the largest share of the swing, and it is the one continent where fertility as well as retention is varied. Exhibit 29 shows the nine African scenarios.

1. The range is 33.0% to 34.6%.About 3.19 to 3.41 billion Christians in 2050. The central case (retention holds, expected fertility) gives 34.3%, in line with CSGC’s own projection ².
2. Retention moves the result about twice as much as fertility.At expected fertility, retention eroding to the US/Chile pattern lowers the 2050 share by 1.3 points (125 million fewer Christians). Moving from fast to slow fertility decline changes it by 0.7 points.
3. The retention rows are not hypothetical.South Africa, Brazil and Mexico already show ‘softens’. The United States and Chile show ‘erodes’ ⁶. The development link in Part 2 (a median 18% switching in very-high-development countries against 3% in low-development ones) makes ‘softens’ the default path as Africa develops, unless something changes ³¹.

The difference collaboration makes. The next question is which retention row Africa ends up in, and when. Without a shared response, the likely path is a drift from ‘holds’ toward ‘softens’ as development raises switching. A collapse of trust could push it toward ‘erodes’. We modelled collaboration as timing: cohorts reaching adulthood before the shared response starts follow the South African drift. Later cohorts keep today’s African retention.

1. Collaboration is worth about 56 million people by 2050.At expected fertility, a fragmented drift to ‘softens’ gives 33.7%. Collaboration that holds retention from 2027 gives 34.2%: 56 million more Christians.
2. Each year of delay costs about 2 million.Starting in 2033 instead of 2027 gives 34.1% (+44 million). Starting in 2040 gives 34.0% (+29 million). Removing duplication shows up mainly as time, and time is measured in people.
3. A collapse of trust costs about 66 million more.If all cohorts follow the US/Chile pattern, the share falls to 33.0%. This is the scenario the Kenyan warning in Part 3 points to.
4. These are stakes, not predictions.The retention rows are observed in real countries. The collaboration pathways are modelled. They show what is at stake if collaboration holds retention. They do not show that it will. JFINDX, with a Belong–Trust module, comparing cities with strong collaborative tables against others over time, is how to test them.

5.4 When: the cost of waiting#Comment

The cost of waiting compounds because each year another cohort reaches adulthood under the fragmented pattern. A shared response that holds retention from 2027 keeps about 120 million more people in the faith by 2050 than the drift. From 2033 the gain is 90 million and from 2040 60 million, about 5 million a year lost between 2027 and 2033 and slightly more after (Exhibit 32). The number measures what holding retention is worth, not what any programme produces, which is why the finding says at stake. The model assumes that a shared response holds retention and computes the value of that. Whether it does is what JFINDX exists to test.

5.5 Who: the generation that decides 2050#Comment

The cohorts that carry the modelled effect are aged 18 to 43 in 2050. They are 0–19 years old in 2026, or not yet born, so they are in children’s and youth ministry now or will be within a decade. About a quarter of them are not yet born and half are under 13. JFINDX picks them up as they come of age: about half of them are inside its 13–30 range by 2033 and two-thirds by 2040 (Exhibit 33), and the index does not stop at 2033, so the trends it records over the next seven years keep directing the response beyond the goal year. That is why the road to 2033 starts with children’s and youth ministry and their parents. The window for the shared response is the next ten years. A baseline in 2026–27 and trend lines by 2030–31 would show, before 2033, whether each continent is holding its row or drifting (Section 6.7).

5.6 Collaborative against fragmented: four levers, four layers#Comment

Our findings point to four collaborative levers, each aimed at one layer of the handover. Together they are the difference between the fragmented and collaborative rows of Exhibit 31.

Why we expect collaboration to work, and where the evidence sits. The claim that working together changes outcomes has been tested outside the church. Kania and Kramer’s 2011 study of cross-sector initiatives found that large-scale social change came from coordinated effort rather than from the isolated work of single organisations, and named five conditions for it: a common agenda, shared measurement, mutually reinforcing activities, continuous communication and a backbone organisation ¹²⁸. A 2018 cross-site study of 25 such initiatives found population-level change in 20 of them. In the eight studied in depth the collective effort had contributed to that change, and backbone support, a common agenda, mutually reinforcing activities and shared measurement were the conditions that went with it ¹²⁹ (Counted: evaluations of civic initiatives in education, health and poverty, not of churches). The Collab was designed on those conditions before this paper was written: one goal for 2033 (the agenda), JFINDX (the measurement), the four levers (the mutually reinforcing activities), a rhythm of calls and gatherings (the communication) and NXT Move as backbone ^{60, 61}. The church’s own movement points the same way. The Cape Town Commitment made partnership a mark of the global evangelical movement ²², and the Fourth Lausanne Congress in Seoul in 2024 closed with more than 6,000 collaborative action commitments and 284 action teams formed across a hundred collaborative sessions ¹³⁰. What no study has yet shown is the link this paper models, between collaboration and the retention of the next generation. The grid states the stakes. JFINDX, comparing cities with strong collaborative tables against others, is the test (Section 5.8).

Unity builds trust, and division spends it. The link between collaboration and the handover is trust, the foundation layer of the model in Part 4, and the case for it is older than the studies. Jesus made the love of believers for one another the mark by which the world would know them (John 13:35) and their oneness the reason the world would believe (John 17:21–23). Francis Schaeffer drew the conclusion in 1970: “we cannot expect the world to believe that the Father sent the Son, that Jesus’ claims are true, and that Christianity is true, unless the world sees some reality of the oneness of true Christians” ¹³³. The counted evidence runs the same way in reverse. Among Americans who attended church as teenagers and dropped out as young adults, 32% said church members had seemed judgmental or hypocritical and 25% that they disagreed with the church’s stance on political or social issues ¹³⁴ (Counted; U.S.). Kenya’s Gen Z left church leadership rather than God, over politicians in the pulpit (Section 3.6), and across Africa trust in religious leaders is lowest among the young ^{51, 41}. A church seen to be divided, or captured, loses the next generation at the layer where decline begins. And collaboration is how trust is rebuilt, not only what it produces. Research on collaboration between organisations finds that trust is built in a loop: small joint actions with modest risk produce results, results raise trust, and higher trust allows larger joint action ¹³⁵. Kania and Kramer’s condition of continuous communication exists for the same reason, because partners need years of regular contact before they trust one another enough to act together ¹²⁸. The Collab’s calls and gatherings and the Nairobi tables are that loop. Lever 3, unity displayed and trust regained, is where the model carries it: a church working together in front of its young people is doing the one thing they were told to look for.

5.7 The ‘grows’ row: what multiplication would add#Comment

The grid has no upside row. It models whether the church keeps the people it has. It does not model net conversion, because Ghana’s small net gain (72 → 73) is the only counted evidence of it in the African data ⁶. But Part 1 shows what sustained net growth has done before, and the arithmetic of what it would do now is simple enough to state.

Net growth changes the share multiplicatively: a sustained net growth rate of g per year from 2033 multiplies the 2050 share by (1 + g)¹⁷. The table applies that to the central case. It is illustrative and Modelled. It assumes world population follows the UN medium path and that the gain comes at the expense of other groups.

The comparison is the point of the paper. Africa’s whole retention swing is 1.3 points, the world’s 2.9 (Section 5.2). Sustained net growth of a quarter of a point a year, about half the missionary century’s rate and a small fraction of the early church’s. The comparison is generous to the target: the missionary century’s gain was mostly births in the Christian heartland (Section 1.6), so a quarter of a point that comes from conversion would be a harder thing than the revival’s generation achieved, and adds 1.5 points by 2050 and 3.8 by 2075, and keeps compounding. Retention is a level: it decides whether the church keeps its third of humanity. Multiplication is a slope. The first protects the line. Only the second bends it. And Part 1’s evidence is that net growth of that order has only ever come from an activated church.

Put per believer, a quarter of a point a year is about one additional person for every 400 Christians each year, beyond keeping pace with the world: about 6.7 million people a year at today’s numbers (Modelled). The early church’s rate, four hundredths of a person per believer per year, was one in 25. No programme in an established church has been shown to produce even one in 400 at scale. The vehicles that plausibly can are new congregations and the lay-led movements that start them (Section 6.6). The largest claimed example, church planting movements reporting about 99.9 million believers in 6.8 million house-sized churches ⁹⁴, would be of that order if much of it were net-new. It is self-reported and Unverified, which makes it a question for measurement, not a number for the grid.

Where multiplication has to happen. The ‘grows’ row does not say where the growth would come from, and it matters. Net growth means people coming to faith who did not have it, and nearly four in five of the world’s non-Christians live in Asia ^{3, 2}. Because Asia holds about 58% of the world’s people and Africa about 19%, a point of Christian share gained in Asia moves the world line about 0.6 points, and a point gained in Africa about 0.2 (Exhibit 37. Modelled at 2025 weights). Africa protects and lifts the level: CSGC’s projected rise to 34.1% by 2050 is largely African ². Sustained growth beyond that requires the church to multiply where it is smallest: in Asia, in the Middle East, and in Africa’s own Sahel and north, most of it inside the 10/40 Window. There are signs of it. CSGC projects Asia’s Christians to grow from 417 million to 582 million by 2050, with the fastest growth in South and South-East Asia, and Mongolia, Nepal and Cambodia among the newest churches in the world ³ (Projected). None of this is in the grid yet. An Asian conversion row for the regional grid is listed as open work (Appendix A.4), parameterised by net conversion rather than by money, because no counted evidence yet links funding to disciples made and kept among the least reached.

5.8 What would prove us wrong#Comment

One test for each headline finding, stated in advance.

• Finding 1. If CSGC’s or Pew’s next revision moves the 1900–2026 share outside the 32–35% band, or shows net growth sustained above zero in any 25-year period since 1910, the flat line is not flat.
• Finding 2. If the regional grid’s retention swing shrinks below one point of the world once tracked cohorts replace the lifetime-switching snapshot, retention is not the lever this paper says it is.
• Finding 3. If activated believers in the JFINDX data (1 : 1 : 1, roles held, something started) do not show higher retention and more new believers than others of the same age and community, activation is not the mechanism.
• Finding 4. If countries and networks that pooled measurement and response after 2027 show no better retention among 13–30-year-olds than those that did not, collaboration is not worth what the grid says.
• Finding 5. If retention among the cohorts reaching adulthood after 2033 proves no different from those before it, the generation is not the hinge this paper makes it.

Three further tests, for the rows and the vehicle.

• Retention data that contradict the rows. If JFINDX with the module finds no trust erosion by age in African cities as they develop, the ‘softens’ default is wrong and the stakes of collaboration are smaller. That is a testable prediction, and we would welcome being wrong about it.
• Roles that do not retain. Section 6.6 argues that holding a role goes with staying and that planting creates roles at scale. If, with the context items in Section 4.3, role-holding does not predict staying once community size, tradition and parents’ faith are allowed for, or if young people in new communities hold no more roles than those in old communities of the same size, the planting argument is wrong and the ‘grows’ row has no demonstrated vehicle.
• Multiplication among the least reached that does not last. The case for resourcing the church where it is smallest assumes that first-generation believers in restrictive contexts are kept, not only reached. We found almost no longitudinal evidence either way. If JFINDX and partner data show new believers in the Window falling away faster than growth adds them, or local multiplication collapsing when outside funding ends ¹¹², the case weakens. Both are testable, and the 10/40 collective already offers JFINDX to its members, run locally and anonymised ¹¹⁸.

6.1 Two jobs#Comment

The evidence sorts into two jobs, and they are not the same job. Retention decides whether the church keeps the third of humanity it has. Across the six continents it is worth about 2.9 points of world share by 2050, and a shared response that secures it is worth about 120 million people (Findings 2 and 4). Multiplication decides whether the line rises. Net growth of a quarter of a point a year from 2033 would add about 1.5 points by 2050 and about 3.8 by 2075, and keep compounding (Finding 3). Retention is a level. Multiplication is a slope. The first protects the line. Only the second bends it.

The global church’s own listening names the same two jobs. Across two years of listening calls and a survey of 1,500 leaders, Lausanne found the need for discipleship by far the most often named gap in Great Commission efforts, and reaching younger generations the second ¹⁰². The leaders’ perceptions are stark: 65–80% said churches in their region teach the Great Commission often or regularly, yet they judged only 15–20% of Christians very active in sharing the gospel and 35–40% never or rarely active, with Christians under 30 less active than their elders ⁴³ (SGC pp. 24–26, Estimated: leaders’ perceptions, not counts of members). Teaching from the front has not produced activated believers.

Retention without multiplication. North America’s Amish keep about 80–90% of their young people and have doubled roughly every twenty years, from about 5,000 in 1900 to more than 350,000 today, with very few converts from outside ^{104, 105} (Estimated). Deep formation and high fertility have produced a growing, faithful community. They have not bent any wider line. Formation that does not turn outward protects the line. Only formation that reaches someone else bends it.

Both jobs need the same thing, and the eighteenth century shows why they need each other. George Whitefield preached to an estimated ten million people on both sides of the Atlantic ¹²² (Unverified). John Wesley joined the people he reached into classes of twelve. Whitefield called his own work planting and asked Wesley to water it ¹²⁴. When they divided over doctrine in 1741 the work divided with them. In 1749 Whitefield laid down the leadership of his side, and he left the Wesleys a token of his “indissoluble union with them in heart and Christian affection” ¹²⁴. The fruit that lasted grew where reaching and keeping were joined, and the missionary era that followed began as a union in prayer across denominations (Section 1.6). The early church did both jobs at once because almost every believer was active ⁹. The strategy that follows is therefore not a programme. It is the deliberate re-activation of the people who are already there, in every region at once, from everywhere to everywhere.

6.2 The sequence: time, trust, truth#Comment

The operating sequence for everything below is the one the evidence in Part 2 forces: Time → Trust → Truth ⁶⁵. Spend time with young people where they are. Earn relational trust, which now carries the weight institutions used to carry. And then present truth in a context where it can be received. The book’s version is “establish trust before presenting truth” ³². The Celtic version was belonging before believing ¹⁵. Ghana’s version is a young generation choosing churches that engage them (Part 3). Two consequences follow for how ministries spend their time. Listening is not a prelude to ministry. It is ministry, and it is measurable (67% of teenagers say their faith deepens when someone listens without judgment, against 33% for sermons ⁶⁴). And relational ministry has to be designed to scale, as programmatic ministry once was, or it stays a matter of a few hundred coffees.

6.3 Four levers in practice#Comment

What the field is already showing. Two lessons from NXT Move’s work in Nairobi, Pretoria and Cape Town in August 2026 belong beside the table ¹³¹. The first is that the levers are being reached for locally before anyone proposes them: two regions, working separately, arrived at the same three moves, to coordinate what already exists, put the next generation at the centre and resource it locally. The second is about money. Leaders in both places concluded that the fundable thing is not any single project but the table itself: the removal of duplication, the shared measurement and the convening, which make the projects that flow through it investable in a way none of them are alone. And a smaller observation that belongs in the same column. The isolated practitioners the team met were exhausted. Burnout is a cost of working apart, and one of the plainer arguments for lever 4.

6.4 Measuring what matters#Comment

The Jesus Following Index (JFINDX) is the shared measurement for the road to 2033: a seven-minute survey of 13–30-year-olds, run by member organisations and pooled, with a country shown once it reaches 2,000 responses. The roadmap runs from a 2026 baseline through proving the model (2027), scale (2028–29) and trend lines (2030–31) to standardisation in 2032–33, at a cost of about one million dollars ^{61, 62}. With the Belong–Trust module it reports the whole handover, belong, trust, depth and lead, by age, every year. The three standards in Section 4.3 (sampling honesty, pre-specification, ethics review) are what make it credible to the readers this paper is written for. The prediction it tests is the one in Part 5: that trust erodes before belonging as African cities develop, and that cities with strong collaborative tables hold the ‘holds’ row while others drift.

6.5 Activation#Comment

The measure of activation is simple, and it is the one the teaching series behind this paper ends with: 1 : 1 : 1. Every believer walks with one person (house), invites one person (temple) and reaches one person (market) ²³. Not three tasks, but one person operating in all three rooms. A church that builds only one room trains its people to be one-third of what they are. It is the irreducible minimum of Acts 2, and it is the modern equivalent of the four hundredths of a person per believer per year that built the early church. It is also what Pentecostal growth has looked like for a century: lay evangelism through personal networks ⁴³. And the house room has a long pedigree: it is the sponsor of the early catechumenate and the class leader of the Methodist revival ^{97, 78}.

From practice to multiplication. Activation is the end of a chain, not a campaign. Believers are formed in a few shared practices. NXT Move’s discipleship material names seven: prayer and devotion, worship, the Word, community, serving, giving and sharing faith ¹⁰⁷. They practise them with someone else (1 : 1 : 1). They do it in a setting small enough to be known, from the Methodist class of about a dozen to the Catalytic Communities NXT Move convenes for youth ministry leaders in Dallas–Fort Worth: monthly cohorts of 10–15 leaders, with a longitudinal study by Dallas Theological Seminary ¹⁰⁸. And the result is counted. For the count we propose three items for JFINDX alongside the Belong–Trust module. In the past month, have you met with someone to help them follow Jesus? Invited someone to a gathering where they could meet God? Shared what Jesus has done in your life with someone who does not follow him? Asked by age every year, they would show whether the house, the temple and the market are active, not only full.

Fast, not hasty. Some current models measure activation by speed. Disciple-making movement networks report more than 100 million professing disciples, about 1% of the world ⁴³ (SGC p. 18, Unverified: reported by the movements themselves), and critics such as Matt Rhodes argue that pressure for rapid generations of churches can bypass teaching and formation ¹⁰⁶. Part 1 points the other way. The early church’s rate was high because formation was patient and almost everyone was doing it. The aim of 1 : 1 : 1 is breadth, every believer forming someone, not haste.

From everywhere to everywhere. Activation inside one region cannot bend a world line (Section 1.7). Sending from within the Window is one of the 10/40 collective’s five goals (Section 1.8). The African church that Part 3 describes is the largest pool of young believers in the world and holds about 3.5% of the church’s income ⁴⁴. Much of Africa’s own least-reached population, in the Sahel and the north, lies inside the 10/40 Window. Chad, half of Part 3’s exception, is a Window country. The sending is already multi-directional. MANI’s continental consultation in Abidjan in March 2026 brought together more than 400 African mission leaders from about 40 countries and affirmed the African church as an increasingly sending force ¹¹⁴. Korea’s churches reported 21,917 missionaries in 174 countries in 2023, a number that has fallen for several years ¹¹⁵. And the SG500 Asia Cities Forum is working toward gospel movements in Asia’s 500 largest cities by 2033 ¹¹⁶. The collaborative task is to connect them: young leaders who are already activated, and the resources and relationships that would let them send as well as stay, and sustain the believers already inside the Window. The 10/40 collective puts it plainly: the Window “does not need more senders” so much as the believers already there, “activated, and multiplying” ¹¹⁸.

6.6 Planting: activation that stays activated#Comment

Activation needs somewhere to happen, and the most reliable place the evidence points to is a church that does not yet exist. This is not a claim that new churches are better than old ones. It is a claim about roles, and about the unit that matters: not churches planted, but believers activated to plant them. Antioch was planted by unnamed refugees (Section 1.2). The Methodist expansion and the Pentecostal century were carried by lay people starting congregations that did not wait for permission (Table A8).

Why new settings activate. A new church has more jobs than people, so everyone is needed. Behaviour-setting research found that where there are fewer people than roles, people take on more roles and feel more responsible for the outcome, first in schools and then in congregations ^{92, 93}. Large congregations show the reverse in one respect: people who attend very large churches report less support they can count on from other members ⁹¹ (Counted, U.S.). And churches age the way Christendom did: roles become professional and members become an audience. A church that stops sending re-runs 313 in miniature.

What the counted evidence shows, almost all of it from the United States:

• Roles and retention. Teenagers who held regular responsibilities or leadership positions at church were more likely to stay through their early twenties (Section 2.5) ⁸⁶ (Counted, correlational).
• Activation and age. Southern Baptist churches founded since 2000 baptise 8.4 people per 100 attenders a year, against 5.1 for churches founded before 1900 ⁹⁰ (Counted; one denomination, 2023; baptisms include members’ children). New churches that start another church within five years report higher attendance and more new commitments ⁸⁷ (planters’ own reports).
• Reach and transfer. In U.S. churches planted since 2008, planters estimated that 42% of worshippers had never attended church or had not attended for many years, and about a third of plants were made up mainly of the previously unchurched ^{87, 88}. In the average U.S. Protestant church today, pastors estimate that 20% of newcomers did not attend church before ⁸⁹. (Estimated, different definitions and respondents, so not like-for-like.) Most people in Western plants still come from other churches. The often-quoted claim that 60–80% of a plant’s people were unchurched has no primary source (Appendix C.1).
• Movements. Church planting movement counts are self-reported (Table A8). The 2020 U.S. national study of disciple-making found no statistically verifiable multiplying churches in North America, and warned that churches over-report their own disciple-making ⁹⁵. Neither confirms nor refutes the global counts. Both argue for measuring them.

Two jobs, one mechanism. Transfer growth is usually counted against planting. On this paper’s thesis it is half the point. A believer who moves from a seat in an established church to a role in a new one has been activated even if no one has yet been converted: that is the retention job. The share of a plant’s people who were not in church before is the multiplication job. Planting does both, in proportions that can be measured. The measure is the planter: how many ordinary believers, above all young ones, have started something (a group, a gathering, a church), and whether what they started has started something else. This extends 1 : 1 : 1 rather than adding a fourth task. Planting is what 1 : 1 : 1 produces when it compounds, when the person reached in the market becomes the house where the next gathering begins.

Three cautions. Selection: activated people choose plants, so the correlations above do not show that planting causes activation. The comparison in Section 4.3 is designed to separate the two. Duplication: a plant beside a healthy church duplicates rather than multiplies. The Collab’s map of who does what (Section 6.3) is where plants are pointed at gaps, above all among the least reached. Durability: new churches age, and the activation they create fades unless they plant in turn, so the measure is generations, not starts.

6.7 The road to 2033#Comment

The budget, governance and division of labour behind these milestones are set out in the JFINDX brief and the Collab’s own working documents, not here ^{62, 60}. This paper’s job is the argument and the evidence.

6.8 The invitation#Comment

This paper was written to rally people to a cause, not to an organisation. The invitation is not to join NXT Move, or to help anyone do what they already do. It is to act on five things the evidence points to, wherever you are, with whoever is near you. People who act on them will find one another.

• Join the conversation. Take the flat line seriously, and talk about it with the people you work alongside: what it would take, in your city and your generation, for the church to grow faster than the world again. The data, the code and the assumptions behind every chart are published with this paper so that the conversation can be a shared one. We would rather be corrected than believed.
• Collaborate. Duplication is the enemy, and time is measured in people. Find the others working toward the same generation in your city and act together: one calendar, one table, one map of who does what, without logos or ego.
• Research together. Measure the whole handover, belong, trust, depth and lead, by age, with a shared instrument, and read the results together. What is understood together gets acted on together. Young people should be co-researchers, not respondents.
• Build meaningful relationships. Time, then trust, then truth. Move time and budget from broadcast to listening. Share the table with young leaders in real decisions. Stay long enough to be trusted. Belonging precedes believing.
• Activate the church. One person to walk with, one to invite, one to reach. Every believer active, in every region at once, sending as well as staying, and sent to start what does not yet exist. Retention protects the line. Only this bends it.