Not really a joke, but this reminded me of how I was almost beaten to death by a penguin when I was ten years old. Since Bible mythology tells us that Mary and Joseph were in Bethlehem due to a empire-wide census/taxation decree by Caesar Augustus, one would have to ask: in the dead of winter? Really? It's far more likely that the decree was issued in the spring or summer. Furthermore, the only way you can determine if anything in the Bible is other than fiction is if it's corroborated by non-Christian sources--and Roman records show no such decree.
When the early Christians were trying to sell their brand to all those pagans, one brilliant marketing move was to let them keep all of their holidays and festivals--they just rebranded them. And every culture had a winter solstice festival. So fine, the Christians said, we'll use that time to celebrate the birth of Jesus. Fine, the pagans said, can we still get drunk? Sure, the Christians said.
So what almost got me killed was this observation, voiced by me during religion class in fifth grade, being taught by a Dominican nun. I said that it was far more likely that Jesus was born in the fall. The wrath of a nun is like none on earth for any blasphemer.
I would much rather be carving Jesus's face into a pumpkin, actually.