Why do some churches grow while others do not? This question gave rise to one of the most influential movements in American evangelical Christianity in the 20th century. Its history shows how easily a question about fruitfulness can become a question about success.
This movement is known as the Church Growth Movement and is associated with the name of Donald McGavran. The son and grandson of missionaries, McGavran spent nearly three decades of his life in India, where he witnessed first-hand what others only saw in statistics. Having been involved in decades of sustained evangelism, he was puzzled by the fact that some local communities were embracing the Christian faith in large numbers while others remained unmoved by missionary efforts.
McGavran managed to formulate an answer, which he set out in his 1970 book Understanding Church Growth, and the sociological premise on which his answer was based continues to have an impact today. He believed that the Gospel spreads most naturally through pre-existing networks of kinship and friendship—”bridges of God” as he called them. He was convinced that people find it easier to embrace the faith when it does not require them to overcome barriers of language, ethnicity, or class. (This model emerges naturally from experiences such as those of Lydia, the Philippian jailer, and Cornelius’s family.)
Building on this insight, McGavran developed the controversial principle of homogeneous unity, evident today in churches where a particular type of believer predominates to the exclusion of others, such as youth churches, ultra-conservative churches, and Roma churches.
Subsequently, expanding on the metaphor of the bridge, McGavran became increasingly preoccupied with the social, cultural, and strategic conditions that facilitate or hinder a response to the Gospel.
Common sense in pastoral ministry
Following the integration of the School of World Mission (which had over 1,200 students in the mid-1980s) into Fuller Theological Seminary, the conceptual framework introduced by McGavran was enriched with tools borrowed from marketing under the influence of Professor C. Peter Wagner.
At that time, marketing was a relatively new academic discipline. The first university courses in marketing were introduced in the United States at the beginning of the 20th century, around 1902–1903. By the 1930s, the field had already developed its own methods and scientific approach. For religious leaders, this move towards marketing was, above all, an attempt to introduce clearer criteria to a field where failure was difficult to explain. Many missionary initiatives with poor results could be shrouded in convenient ambiguity. Leaders who refused to confuse zeal with the fruits of the mission therefore began to seek clearer evaluation criteria. Marketing seemed to offer exactly what was missing: more method and accountability for results.
Churches learned to identify a target audience and study its felt needs. In order to better meet these needs, churches were also encouraged to remove “barriers to growth”—that is, intimidating buildings, obscure ecclesiastical vocabulary, inaccessible music, and long services. Throughout this process, the role of the pastor gradually transformed from that of a teacher of Scripture to that of a visionary leader of an organisation with measurable growth.
Then, in 1988, George Barna published Marketing the Church, in which he established the new language more explicitly. Churches were treated as providers and people as consumers with diverse needs. Evangelism was conceived as a sales funnel involving prospects, visitors, return visitors, members, volunteers, and donors. Barna’s manuals and the practical framework offered by pastors Bill Hybels (at Willow Creek Church) and Rick Warren (at Saddleback Church) popularised this approach so much that it became the equivalent of common sense in ministry for an entire generation of pastors.
However, anticipating this shift, the English sociologist Os Guinness warned in his 1993 book Dining with the Devil: The Megachurch Movement Flirts with Modernity, that the church risked succeeding in terms of its methods but failing in its message to the world. To serve the age is one thing, and to become its prisoner is quite another, Guinness would reproach. Yet his voice remained marginal for two decades, until the method began to reveal its own limitations.
The invisible filter
The 1960s and 1970s brought a restlessness that could not be ignored in American Protestant churches. Traditional forms of community life were losing their strength and many congregations seemed increasingly disconnected from the cultural changes around them. The Church Growth Movement offered an appealing answer based on greater rigour, more attention to context, and concrete tools through which the needs and outcomes of the community could be observed, measured, and evaluated. However, in introducing these new tools, the movement unintentionally placed an axiom at the centre of church life, upon which pastoral priorities were set, decisions were made, and judgements were passed about what constitutes a healthy church.
At the height of the movement’s expansion, this axiom held that spiritual growth equalled numerical growth. From a certain perspective, the approach seemed to be working. The number of American megachurches increased from around 50 in 1970 to 310 in 1990 and approximately 1,250 in 2007, reaching 1,800 by 2020. However, it was precisely this visibility of success that made its cost harder to see.
Over time, concrete love for real people—whose rhythms and unpredictability elude any methodology—became increasingly difficult to integrate into this managerial perspective. Unfortunately, not even fidelity to the individual, where it truly existed, could prevent negative consequences. After two generations, they became apparent.
The Reveal Report
An internal assessment of Willow Creek Church, made public in 2007 and known as the Reveal Study, used the movement’s own empiricism to measure its effects. It found that people’s involvement in church-organised activities was a poor indicator of their spiritual growth.
While megachurches had gained members, American Christianity as a whole was losing ground, as the proportion of Americans identifying as Christian continued to decline. According to the Pew Research Center, by 2019, around 50 million adults who were raised Christian had abandoned this religious identity. One of the most incisive analyses of this phenomenon examines the generation raised in “seeker-sensitive” churches. Their parents had joined communities that were constantly adapting to the needs of their congregants. Once they became adults, their children discovered that the logic of personal choice also applied outside the church, where they sometimes found more compelling alternatives.
In their book Soul Searching, Christian Smith and Melinda Lundquist Denton offered an even harsher assessment. Many young Americans had not rejected religion itself, but had simply stopped receiving the truths of historical Christianity through it. Their faith more closely resembled what the authors termed “moralistic therapeutic deism”—a benevolent, unobtrusive, and helpful God, invoked primarily so that people could be good, at peace with themselves, and happy. The gospel had become so diluted that it could no longer provide them with a foundation or consistent consolation. Once it had reached this status, it inevitably came into competition with society’s other promises of meaning and solace.
However, an important gain also emerges from this negative picture. When taken to its logical conclusion, the movement’s empirical honesty ended up correcting even its own reductionisms. The method was therefore not useless, but had become problematic because of what it measured and what it left out.
The maturation of CGM shows that churches must continue to measure things, but with greater discernment. They should not just focus on what is visible, quick, and easy to quantify, but also on what truly matters for Christian formation.
Recovering the qualitative dimension
One of the most severe warnings comes from Dietrich Bonhoeffer, and this is no coincidence. In 1939, when he published Life Together and Psalms: The Prayerbook of the Bible, the word “community” had already been hijacked by the ideologies of the era. For this reason, his warning carries special weight. “Those who love their dream of a Christian community more than they love the Christian community itself become destroyers of that Christian community,” said the German theologian and pastor. The ideal can blind you, preventing you from seeing the real person standing before you. Similarly, once absolutised, a performance metric can replace the person with a number.
A church can count how many people attend. However, it would also be beneficial to ask how many of them are engaged in a genuine discipleship process—that is, the development of faith and daily life. How many people went through a crisis last year and found more than just a well-organised programme in the church? How many have a friend in the church who truly knows what is going on in their lives?
In Natural Church Development, Christian Schwarz observed that the health and organic growth of a church are more closely linked to the quality of loving relationships among members than to communication strategies or investments in buildings, after studying over a thousand communities in thirty-two countries. Love thus becomes one of the most concrete signs of growth. This is the long-awaited statistical confirmation of Jesus’s words: “By this everyone will know that you are my disciples, if you love one another” (John 13:35).
In the early days of Christianity, Christians were recognised by their care for people outside their own families, which was difficult to explain sociologically and devoid of any obvious expectation of reciprocity or gain. In Center Church, Timothy Keller adopts Francis Schaeffer’s idea that the Christian community is “the final apologetic,” in other words, the place where the invisible truth of faith becomes visible through the way people love those from whom they have nothing to gain.
More than a century earlier, Ellen White articulated the same insight in The Ministry of Healing, writing that “the strongest argument in favor of the Gospel is a loving and lovable Christian”. Although they come from different church traditions, Keller and White both conclude that a community’s apologetics begin with its character.
Resistance to premature segregation
Lesslie Newbigin, a British missionary who spent decades in India and returned to the West with the clear-eyed perspective of an outsider, argued in The Gospel in a Pluralist Society that the Church’s very existence—through this inexplicable association that defies the usual logic of class, race, interest, or social affinity—makes it credible. The Apostle Paul explicitly states in his letter to the Ephesians that, in the body of Christ, the wall between Jews and Gentiles is torn down (Ephesians 2:14).
The diversity of the early Church was a testament before it was a strategy. A congregation in which a retired teacher, a rural student, a businessman, and a single mother come together, listen to one another and care for one another is a phenomenon that sociology can describe but which Christianity can explain practically by focusing on Christ’s way of loving.
A community that learns to embrace people’s genuine differences becomes healthier and stronger than a community meticulously crafted around a homogeneous target audience.
No matter how useful the methods may be, optimising and loving are profoundly different things: love stands by the person, even when their presence disrupts the plan.
Perhaps that is why the greatest challenge facing Protestant churches is to continue counting, organising, communicating, and learning from their own results without forgetting that the people they invite to cross their threshold are, above all, their neighbours. When it comes to one’s neighbour, the ultimate criterion remains love.