As far as I know, oysters were not a biblical foodstuff. As members of the shellfish category, oysters are not, of course, kosher. But I don't think anybody in the early Christian world used to eat them. It wasn't until Roman times in France (Cancale in Brittany) and Britain (Whitstable in Kent) that humans got around to consuming this weird creature. Why is it, then, that people here in France have the habit of gobbling down huge quantities of oysters at Xmas celebrations?
On Xmas eve, for example, friends dropped in for a drink... with a bag of oysters, which I promptly opened. This morning, for Manya and me, I opened another couple of dozen oysters.
There are other traditional Xmas foodstuffs in France, such as chapon (castrated rooster) and foie gras, but I've always had the impression that the true gastronomic spirit for end-of-year festivities involves oysters. Why is this so? Is there some special reason why French oyster farmers have decided to concentrate upon this particular time of the year to bring their produce to market?
Oysters have always had a reputation, rightly or wrongly, as an aphrodisiac product. That might be the reason why they're associated with this festival that celebrates the birth of a child. But this explanation has two obvious weaknesses. First, the season of lovemaking would have been nine months earlier on. Second, in the case of the offspring named Jesus, we're told that there wasn't any lovemaking at all. So, my theory's not very good. Maybe somebody has a better explanation for all these Xmas oysters...