Three Centuries Without a Sword

This book is a work of nonfiction. Every text quoted is real and cited; the reader can verify every reference in any decent library or in the standard online critical editions. Every archaeological site mentioned is real. Every numerical estimate-growth rates, community sizes, traveling distances, communication latencies-is sourced from the contemporary academic literature.
The book makes one strong empirical claim and one careful theological caveat.
The empirical claim is this: between approximately 33 CE and approximately 313 CE, the Christian movement grew from a small group of disillusioned Galileans hiding in an upper room in Jerusalem to roughly six million members spread across the Roman Empire from Britain to Persia, accomplishing this growth without the use of military force, without state power, without mass communication technology, without economic coercion, and-for most of the period-against active legal and social opposition. The growth math has been carefully reconstructed by sociologists of religion (Stark 1996 and after), and the mechanisms of propagation have been examined by historians of late antiquity (MacMullen 1984, Hopkins 1998, Bagnall 2003, and others). The reconstruction works only if we take seriously what the early Christian sources themselves say about how the spread occurred: through preaching, through perceived signs of supernatural power, through unusual communal life, through the witness of those who died rather than recant, and through the patient transmission of testimony from one named individual to the next.
The theological caveat is this: showing how Christianity spread does not, by itself, prove that the underlying claim is true. Many movements have spread effectively. Some of those movements were built on truths; some on partial truths; some on falsehoods. The empirical question about how the spread occurred is methodologically separate from the metaphysical question about the truth of the spread's content. This book undertakes the empirical question and points the reader toward where the metaphysical one can be continued.
I write as a French Catholic from Lorraine, with the formation that comes from being raised a few kilometers from Domrémy-la-Pucelle, where Jeanne d'Arc was born in 1412. Her line to her judges, "Vous avez votre conseil, et j'ai le mien"-"You have your advisers, and I have mine"-is, in my judgment, the same answer the apostolic generation gave the Roman provincial governors who interrogated them. The pattern of refusal recurs across the centuries. So does the pattern of spread. This book examines the spread.
What you decide after reading is your own.