1.  As with most superstitions, many reasons have been given to justify the myth that when a Friday is the 13th day of a month it is unlucky. This myth is usually associated with two causes, the fear of the number 13 (triskaidekaphobia) and the belief that starting ventures on Fridays was bad luck. Combined, they are supposedly doubly bad.

2.  Not actually unlucky, but rather a good day combining the symbolisms of Friday and 13. The superstition was manufactured to turn Christians from the Old Religion, and make them fearful of the teachings of Love and Fertility. Friday is the day of the Nordic Goddess Frigga, or Freya, who is the equivalent of the Roman Venus—Goddess of Love. And 13 is associated with both the size of the traditional Witches’ coven and the 13 Full Moons to a year—in other words, the fullness of Life.