A lot of hotels and skyscrapers don't have a thirteenth floor -- they go straight from twelve to fourteen, and some grocery stores don't have an Aisle 13. Many fisherman and sailors believe it's bad luck to begin a voyage on a Friday, regardless of the date. Back in 1306, King Philip of France had hundreds of Knights Templar arrested on Friday, October 13. They were tortured and then executed - which I would say indeed qualifies as a stroke of bad luck.
While Friday the 13th may be bad luck for some, some witches and Pagans see it as a magical date. Friday is named for Freyja, a Norse goddess of fertility (sometimes called Frigg). The ancient Egyptians associated the number thirteen with immortality -- there were twelve steps on the ladder to eternal life and knowledge; the thirteenth step meant going through death into everlasting life. In Rome, it was traditional to have thirteen guests to be present at weddings. In the Hebrew faith, age thirteen is when a young man or woman is finally considered an adult. Finally, thirteen has a strong association with the moon for many of us. There are thirteen lunar cycles each year, and many of us celebrate the full moons with an Esbat rite. Thirteen is the traditional number of witches in a coven.
David Emery, our Guide to Urban Legends, has some great stuff about Friday the 13th Legends and Folklore - check it out if you get a chance!
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