I've been reading The World of Rome
So what does Grant have to say? Here's an excerpt:
It is easy to point to resemblances between the Greco-Roman Mystery faiths and Christianity, which emanated from the same world as theirs and sought to answer the same needs. For instance, the Christian and pagan worships answered similar demands for mutual support and posthumous guarantees, and sought to satisfy many of the same cravings--for a protector who was above Fate, for a priviliged status such as the world could not give, for revelation, and for an effective ritual.Grant talks a good bit more about the similarities of various religions, and the reasons why someone trying to decide who to believe would have a hard time choosing. Then he goes on:
But the real strength of Christianity, the truly unique and exciting feature which in the end caused it to outstrip all other religions, was its Founder's message of love--profoundly original in its emphasis despite all that it has selected from earlier Rabbinical teachings. . . . The Greco-Roman philosophies and religions . . . had not presented so gloriously definite a promise of immortality.I could quote a lot more here but I think you get the picture. To sum it up, Grant says many of the religions of the time had very similar teachings, and that they borrowed liberally from each other. The Christians emerged dominant because they added just a few new, different twists.
I really don't think Grant intended it this way but the way this comes across to me is that the Christians nailed the marketing. They copied a lot from the religions that preceeded them, they tweaked things just a bit to differentiate themselves, and they got it right. Forget about having "The Truth," they had a good PR director.
You may disagree, and you may want to send me nasty email (not a very Christian thing to do, however), but I'm not claiming revealed truth here. I'm just telling you how it struck me.