I know that many cities do not have a 13th Street or a 13th Avenue. Many buildings don't have a 13th floor. 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). There are 13 witches in a coven. There were 13 people at the Last Supper.
Not enough.....
Twelve gods were invited to a banquet at Valhalla. Loki, the Evil One, god of mischief, had been left off the guest list but crashed the party, bringing the total number of attendees to 13. Anyone who has seen The Mask knows what Loki is.
More....
It was on a Friday, supposedly, that Eve tempted Adam with the forbidden fruit. Adam bit, as we all learned in Sunday School, and they were both ejected from Paradise. Tradition also holds that the Great Flood began on a Friday; God tongue-tied the builders of the Tower of Babel on a Friday; the Temple of Solomon was destroyed on a Friday. In pagan Rome, Friday was execution day (later Hangman's Day in Britain).
More.... (The one I know)
One theory, most recently propounded in the novel "The Da Vinci Code," holds that it came about not as the result of a convergence, but a catastrophe, a single historical event that happened nearly 700 years ago. The catastrophe was the decimation of the Knights Templar, the legendary order of "warrior monks" formed during the Christian Crusades to combat Islam.
Renowned as a fighting force for 200 years, by the 1300s the order had grown so pervasive and powerful it was perceived as a political threat by kings and popes alike and brought down by a church-state conspiracy, as recounted by Katharine Kurtz in "Tales of the Knights Templar" (Warner Books: 1995):
"On October 13, 1307, a day so infamous that Friday the 13th would become a synonym for ill fortune, officers of King Philip IV of France carried out mass arrests in a well-coordinated dawn raid that left several thousand Templars — knights, sergeants, priests, and serving brethren — in chains, charged with heresy, blasphemy, various obscenities, and homosexual practices. None of these charges was ever proven, even in France — and the Order was found innocent elsewhere — but in the seven years following the arrests, hundreds of Templars suffered excruciating tortures intended to force 'confessions,' and more than a hundred died under torture or were executed by burning at the stake."
THE TRUTH:
Jason is coming and he is going to kill you.