Fear of Friday the 13th is rooted in ancient, separate bad-luck associations with the number 13 and the day Friday. The two unlucky entities combine to make one super unlucky day.
A particularly bad Friday the 13th occurred in the middle ages. On a Friday the 13th in 1306, King Philip of France arrested the revered Knights Templar and began torturing them, marking the occasion as a day of evil.
There is a Norse myth about 12 gods having a dinner party at Valhalla, their heaven. In walked the uninvited 13th guest, the mischievous Loki. Once there, Loki arranged for Hoder, the blind god of darkness, to shoot Balder the Beautiful, the god of joy and gladness, with a mistletoe-tipped arrow. Balder died and the Earth got dark. The whole Earth mourned.
In ancient Rome, witches reportedly gathered in groups of 12. The 13th was believed to be the devil.
Many triskaidekaphobes, as those who fear the unlucky integer are known, point to the ill-fated mission to the moon, Apollo 13.
If you have 13 letters in your name, you will have the devil's luck . Jack the Ripper, Charles Manson, Jeffrey Dahmer, Theodore Bundy and Albert De Salvo all have 13 letters in their names. (ok, so that one gave me the chills.)
What are your favorite superstitions?
This is one of my favorites. It has worked on all of the babies born into the Gerety/Young households with one exception. Me.
To predict the sex of a baby: Suspend a wedding band held by a piece of thread over the palm of the pregnant girl. If the ring swings in an oval or circular motion the baby will be a girl. If the ring swings in a straight line the baby will be a boy