The sixth day of the week and the number 13 both have foreboding reputations said to date from ancient times. It seems their inevitable conjunction from one to three times a year (there will be two such occurrences in 2013, exactly 13 weeks apart) portends more misfortune than some credulous minds can bear. According to some sources it's the most widespread superstition in the United States today. Some people refuse to go to work on Friday the 13th; some won't eat in restaurants; many wouldn't think of setting a wedding on the date. So be warned if you decide to do either.
LEGEND HAS IT: If 13 people sit down to dinner together, one will die within the year. The Turks so disliked the number 13 that it was practically expunged from their vocabulary (Brewer, 1894). 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.