There are several theories about Friday's misfortune, but we certainly don't know which theory may be what makes us think this day is unfortunate. According to one theory, it was an unfortunate Friday the 13th because 13 people were sitting at the table at the last dinner. True, this only shows the misfortune of the number 13, it has little to do with Friday. According to another theory, on Friday, October 13, 1307, the King of France issued an arrest warrant against the Knights Templar, who were then tortured and burned at the stake. Maybe that’s the theory that fits better with the superstition related to Friday the 13th.