The Surprising Growth of Christianity – an Excerpt from The Patient Ferment of the Early Church

The following is an excerpt from Alan Kreider’s The Patient Ferment of the Early Church.


No one disputes that the early church was growing, but its growth is hard to measure. For a long time scholars assumed that Christian growth was so rapid that in the early fourth century, on the eve of the emperor Constantine’s accession, five to six million people—between 8 and 12 percent of the imperial populace—were Christian. The most confident statement of this approach was given in the 1990s by a sociologist, Rodney Stark, who calculated that for the church to reach this level, it grew across the first three centuries by 40 percent per decade.

Stark’s confidence has attracted wide assent but also withering criticism, not least from ancient historian Ramsay MacMullen, who has demanded solid, archaeological evidence and posited a much smaller Christian number by AD 310. Debates and speculations will continue as scholars study particular areas in detail. For now, we can safely assume three things:

Cover Art• Christian numbers were growing impressively in the first three centuries.

• This growth varied tremendously from place to place. In certain areas (parts of Asia Minor and North Africa) there were considerable numbers of Christians. But in other areas there were few believers. And some cities, such as Harran in Mesopotamia, were known to be virtual “Christian-free” zones.

• By the time of Constantine’s accession, the churches not only had substantial numbers of members; they extended across huge geographical distances and demanded the attention of the imperial authorities.

It is not surprising that this movement—both growing and worldwide—was buoyant and confident.

We tend to assume this growth and to forget how surprising it was. Nobody had to join the churches. People were not compelled to become members by invading armies or the imposition of laws; social convention did not induce them to do so. Indeed, Christianity grew despite the opposition of laws and social convention. These were formidable disincentives.

In addition, the possibility of death in persecution loomed over the pre-Constantinian church, although few Christians were actually executed. In many places baptismal candidates sensed that “every Christian was by definition a candidate for death.” More generally, as Kate Cooper has pointed out, Christians knew that they, as members of a “dubious group,” were vulnerable to being “turned in” by their neighbors or by others who wanted to see them deprived of privileges. In the 240s Origen commented about the “disgrace among the rest of society” that Christians experienced. Christians had to be cautious.

Nevertheless the churches grew. Why? After 312, when the emperor Constantine I aligned himself with Christianity and began to promote it, the church’s growth is not hard to explain. But before Constantine the expansion is improbable enough to require a sustained attempt to understand it. The growth was odd. According to the evidence at our disposal, the expansion of the churches was not organized, the product of a mission program; it simply happened.

Further, the growth was not carefully thought through. Early Christian leaders did not engage in debates between rival “mission strategies.” The Christians wrote a lot; according to classicist Robin Lane Fox, “most of the best Greek and Latin literature which remains [from the later second and third centuries] is Christian.” And what they wrote is surprising. The Christians wrote treatises on patience—three of them—that we will study in this book. But they did not write a single treatise on evangelism.

©2016 by Alan Kreider. Published by Baker Academic. Unauthorized use of this material without express written permission is strictly prohibited.


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