Some historians have claimed it was the day Eve bit the apple, the great flood began and possibly when the Tower of Babel was started. But a few things pushed it beyond that gentle superstition. The n umber 13 has been considered unlucky since before Jesus walked the earth. Do you know why Friday the 13th is considered unlucky? I did a little research and here’s what I discovered. Happy Bad Luck Day! Isn’t that what Friday the 13th is?