The early Christian movement achieved unprecedented growth during the second and third centuries A.D. Numerous historical and sociological explanations have been advanced to account for this phenomenon and its role in the eventual “triumph” of Christianity under Constantine. Long overlooked in this endeavor has been the role of several spectacular disasters that hit the empire in this same period. Most notable are two periods of widespread and devastating epidemic that hit especially hard in the eastern provinces in the 160s and again in the 250s. This article suggests that the fabric of Roman society was substantially disrupted and demoralized by these catastrophes, and that this opened the door for Christian ascendancy, both theologically and numerically. To demonstrate this contention the character of the epidemics will be described. Then, three main theses will be advanced and explored.
First, the Christians offered a more satisfactory explanation of the catastrophic events. Second, Christian values of love and charity were translated into practices of social service in the times of crisis, thereby creating a network of medical care. Third, with even minimal medical attention, the survival rate among the Christians (and any of their pagan neighbors whom they treated) was substantially higher than that in the general population. Over time, the proportion of Christians in the total population was thereby dramatically increased. When coupled with the network effect of those pagans now disengaged from traditional ties and attracted by Christian benevolence to new attachments, the result was to alter irreversibly the balance of the Roman empire.
Rodney Stark, “Epidemics, Networks, and the Rise of Christianity,” ed. L. Michael White, Semeia 56 (1991): 159.