Legend has it that one should never invite 13 guests to dinner. If one does so, the first guest to get up will die within a year. The Last Supper and the crucifixion of Jesus qualify this superstition to a certain extent. Judas Iscariot, the traitor, was the 13th dinner guest at the Last Supper. Jesus was crucified the next day, a Friday. Hence, many Christians consider this day unlucky.
There is another Norse Myth supporting the superstition of not inviting 13 dinner guests. The legend goes –