We talked about this a little in a folklore class once. Urban legends differ from religious mythos in a couple of fairly basic ways, although there are pretty strong similarities which have already been laid out.
First off, mythos tends to be fairly static, while urban legends tend to be very fluid. The stories a religion tells don’t change. Religions pick a story and stick to it, for lack of a better phrase. Jesus turned water into wine 2000 years ago, and the story hasn’t been updated to include whiskey and Coke, or rocks into cheese logs, or whatever. Urban legends, however, change with the times, updating themselves to fit current events. The black-guy-in-the-elevator-with-the-two-old-white-women story, for instance, has been told about every black celebrity from Reggie Jackson to Eddie Murphy to Dennis Rodman.
Secondly, as has been pointed out, religion by definition contains an element of the supernatural. Urban legends, however, tend to revolve around stuff that can be explained entirely by human nature, the good bits and bad bits. The heroes don’t win out because they’re blessed or divine–they win out because of luck, or cleverness, or bravery. The villains aren’t devils, they’re maniacs, or stupid people, or satanists.
Also, religion tends to give us the names of specific people who did specific things at specific times. We can’t really verify these names and dates because of lack of historical records, but we can tie them to specific historical events. Urban legend tends to be more amorphous, involving my cousin’s friend’s father’s boss’s roommate, this woman in Denver, or the ubiquitous friend of a friend. No names or dates, usually, and if there are names and dates, someone else has heard the exact same story with different names and dates.
There were some other differences, but the class was five years ago, and they escape me at the moment.
I do, however, remember the professor going through this huge list of common characteristics of the heroes in folklore–most of them applied to figures from ancient religions like Hercules, and every single one of them applied to Jesus. Make of that what you will.
