From Richard Carrier's Essay, "Establishing the Biblical Literalism of Early Christians":

Richard Carrier establishes the fact that early Christians really believed their miracle stories, contrary to liberals who demythologize the Gospels like Rudolph Bultmann and John Dominic Crossan:


Usually I don’t have to argue this because it’s obvious. But there are a few who have attempted to contend that early Christians—say, before the fourth century—never took the Gospels as factually true reports of events but only as allegorical tales, fables conveying a point or deeper truth—essentially, as edifying fiction. Some have even strongly asserted there is no evidence of anyone in that time ever treating the Gospels as historical fact. This is so wildly false I am astonished and perplexed by anyone saying this, particularly when they are erudite, well-trained scholars. But every once in a while this happens: someone assertively insists well-established premises of a field I’m in are false, requiring me to do the work of culling enough of the rather obvious evidence we otherwise take for granted just to put such things to rest and demonstrate that, yes, this time, the premise is a correct assumption of the field, not a sectarian contrivance or modern conceit (and remember, I am always ready to admit when it is not).

To be clear, my argument to follow is not that ancient Christians were radical fundamentalists who rejected every allegorical interpretation of tales in their Bible. Every Christian accepted some things in their stories were edifying fictions, or that they were both literally true and allegorically meaningful (I give extensive evidence of this in On the Historicity of Jesus, Chapter 4, Element 14). But my point here on out is that all extant Christian literature from the first two centuries of the religion, every single text that conveys any position on the matter at all, consistently insists the Gospels are substantially records of historical facts. And they often even insist that anyone who denies this is a loathsome fool damned to hell. Even if those same Christians will give an allegorical meaning of a story here and there, that does not counter my point: that none say the Gospels are wholly allegory, or that anyone can be saved believing they are. Ironically, their shrill insistence on this proves other Christians existed who did think the Gospels were entirely a sacred fiction. But we don’t get to read anything those Christians wrote. They were the enemy, all but erased from history, by that other faction of Christianity that came to dominate the world....We can therefore never say “early Christians simply did not regard the Gospels as historical records.” Put that claim to rest. The evidence against it is vast and unassailable. It simply is not true.