I agree, it’s been a great debate so far, with plenty of constructive Christian responses.
As for this particular subject, I know the infancy narratives are less relevant to the thesis of my OP but I can’t let the subject pass without indicating just how strong the evidence against you is on this one. Please do respond if you want to discuss it
First off, I find it astonishing that Christians can defend the Magi story without in any way referring to the fact that it’s based in its entirety on the discredited science of astrology. Stars don’t give you information about momentous world events. Full stop, end of debate. We need go no further than that to establish that this story is pigswill.
But let’s imagine that the story were plausible. Even then, the problem Christians have here is much worse than simply a few dodgy parallels. Infancy narratives everywhere, throughout the ancient world, show a strong tendency to be unhistorical where they appear. This is partly due to high infant mortality; it was a waste of time to document peoples’ birth and infancy because chances were they’d die before they got much further. When interest in infancy narrative emerges, it is typically a long time after the person in question has become famous, when all extant information is unreliable. Which is why most infancy narratives are crap.
In other words, the Bayesian priors are strongly against any ancient infancy narrative, even an ostensibly kosher narrative, being historical. This isn’t an ostensibly kosher narrative. Therefore Christians have an overwhelming burden of proof in this case which they usually fail to recognise and which “could have” scenarios don’t counter.
In addition, fiction tends to display specific patterns and as we would expect, these patterns manifest very strongly in infancy narratives. Infancy narratives are almost always written in such a way as to in some way foreshadow the future or nature of the person involved. Dreams often play a crucial role. Why should real events follow the conventions of contemporary myth? Reality doesn’t work like that.
Furthermore, the evidence shows that historical plausibility isn’t nearly as significant as Christians want us to believe. For instance, Donatus in his life of Virgil begins a clearly fictitious infancy narrative by giving the month of Virgil’s birth, the consuls at his birth and the region where he was born, and is thus grounded in a precise and accurate historical setting. This clearly negates your insistence that historical “plausibility” can redeem a story with all the trappings of fiction.
As an added bonus, early Christians have done us the favour of writing a second infancy narrative (Luke 1-2) which contradicts almost everything Matthew says and throws in a few gratuitous historical inaccuracies of its own.
This is why even centre-ground Christian scholars like Raymond Brown agree with me on this one. The infancy stories are among the most historically indefensible narratives in the New Testament.