How did Friday the 13th become unluck?

Answer 1

First,lets' talk about twelve. People think twelve is a perfect number that there're twelve mouths in a year, twelve constellations all together, and Jesus has twelve apostles.However threeteen which is over twelve is transgression.Therefore threeteen is a symbol of unluck.In the human history,ther were many evil events happen with 13,such as there are 13 people in the last dinner of Jesus,American space ship Apollo 13 has accident when landing off at the moon,these things make western people think once more that this number,13 is unlucky. I am sorry that I only know why eople think 13 is a symbol of unluck but I don't really know about "Friday".Hope this can help you a bit.