Rise of Christianity: A Sociologist Reconsiders History (review)

In this electrifying book, an eminent sociologist of religion “introduce[s] historians and biblical scholars to real social science, including formal rational choice theory, theories of the firm, the role of social networks and interpersonal attachments in conversion, dynamic population models, social epidemiology, and models of religious economies” (p. xii). The result is stimulating, provocative, even revolutionary.

The study begins with an estimation of the numbers involved in the early Christian movement. While hard numbers initially seem irretrievable, Stark works backwards from an estimate of 5–7.5 million Christians in the fourth century to a starting number of 120 (derived from Acts 1:14–15). This estimated growth rate of 40% per decade encourages our confidence since it corresponds so closely with the rate maintained by the Mormon church over the past century (pp. 3–7). A chart demonstrates how “the extraordinary features of exponential curves,” can account for the late third century perception of a tremendous increase in absolute numbers of Christians, without having recourse to theories either of miraculous intervention or of the pivotal importance of the conversion of Constantine (pp. 7–12).

Growth rate implies conversion. But why did people convert? Stark finds deprivation theory persuasive as long as two quite different aspects of human want are acknowledged: while desiring rewards that are scarce (like wealth or health), people also desire rewards that are absolutely unavailable (like immortality). This latter desire “explains why the upper classes are religious at all” and are among those most often drawn to cult movements (pp. 32–37). But what of the mission to the Jews? Long tagged a failure, Stark suggests, to the contrary, that large numbers of Jews did convert. Assuming that the attraction of Christianity for Hellenistic Jews was little different from that of Reform Judaism for nineteenth century Jews, he claims Christianity’s appeal lay in its retention of much of the content of both Judaism and Hellenism, while stripping away the ethnicity that relegated Jews to social marginality. Compared to Philo’s allegorized Judaism, Christianity’s vigorous otherworldly faith offered explanations for natural disasters as well as a hopeful scenario for the future (pp. 51–74).

Conversion to Christianity was also facilitated by the higher percentage of women in early Christianity, due not only to over-recruitment but also to the condemnation of abortion (which was often lethal to the woman) and exposure (which was usually of girls). The relative dearth of women in the surrounding society along with Christian tolerance of exogamy invites us to posit a high number of secondary conversions as well as an enhanced fertility rate among Christians (pp. 100–128).

We know that early Christianity was predominantly an urban movement, but were there specific “characteristics of cities [that] were conducive to Christianization” (p. 129)? In answer, Stark points to the “acute disorganization of Greco-Roman cities” largely caused by extraordinary congestion. The urban density of Antioch at the end of the first century, he estimates at 117 inhabitants per acre, whereas modern New York City has only 37. Calcutta forms a closer comparison with 122 persons per acre (pp. 149–50). The consequences of such crowding are not only dirt and rampant disease, but tendencies to crime and riot. To this scenario of human disorder, we must add such frequent natural disasters as fire, earthquake, and famine (pp. 154–61). Christianity’s success can be attributed, at least in part, to its response to urban chaos and misery.

But what enabled Christians to risk their own health and resources? Stark answers by appealing to “rational choice theory” which suggests, counter-intuitively, that “the more expensive the religion, the better bargain it is” (p. 167). Costly demands tend to produce vital religious groups by effectively excluding those with low levels of commitment and participation. By asking much of its members, Christianity generated a strong sense of belonging as well as substantial resources (pp. 177–88). Members complying with the demand to assist those...