The question I had and have is how Christianity managed to grow exponentially from the time of the apostles up to the early fourth century, when everything took a radical turn with the conversion of the emperor (which led, before century’s end, to Christianity becoming the state religion!). If we assume that the New Testament is basically right, just for the sake of the argument (and in this it cannot be wrong by much, any way you look at it) that sometime after Jesus’ death around the year 30 there were, say, 20 followers who believed that he had been raised from the dead and was exalted to heaven as the Lord, how is it that by the time of Constantine, less than 300 years later, these 20 had managed to grow to make up 5% of the Empire or so – that is, 3 *MILLION* Christian (if the empire is 60 million people, as most historians guess, and Christians at that point were about 1/20 of the total, again, as good historians guess, for a variety of reasons).
How do you get from 20 to 3,000,000, in just under three centuries? That’s the question I was trying to address. And the more I think about it, the more interesting the problem becomes. What exactly were these Christians saying (or doing) that was so compelling? I know what conservative theologians and believers would say, but my question is what historians (whether believers or not) would say. Let me stress, this is a matter of ongoing interest among scholars: I mentioned three of the important books in my previous post, and there are others! But none, in my opinion, quite nails it.