Friday-the Thirteenth has long been considered extremely unlucky because it has some bad associations which came from mythology，tale of the Bible，and the customs and habits. According to the Bible，the Lord God created the first man，Adam.Then he took a rib from Adam's body and out of it created the first woman， Eve. It was said that Adam was created on a Friday and it was on Friday that Adam and Eve ate the forbidden fruit，and on a Friday they died.
Friday was also the common day in England for executing criminals ， for which it was sometimes known as Hanging Day.
From the old Norse myth people got the idea that 13 people sitting at a table to have a dinner was unlucky. And this superstition was confirmed by the last supper of Christ and his disciples. Bible tells us that Christ sat down with his 12 disciples， which made up the number 13， at the last supper when Judas， one of the 12 disciples ， sold his master for thirty pieces of silver. Christ was killed by nailing on the cross the following day on a Friday.
