There are alot of people that are superstitious about Friday the 13th. However not many have a full understanding of the significance of this day. It has been suggested that Friday has been considered an unlucky day because, according to Christian scripture and tradition, Jesus was crucified on a Friday.
The actual origin of the superstition, though, appears also to be a tale in Norse mythology. Friday is named for Frigga, the free-spirited goddess of love and fertility. When Norse and Germanic tribes converted to Christianity, Frigga was banished in shame to a mountaintop and labeled a witch. It was believed that every Friday, the spiteful goddess convened a meeting with eleven other witches, plus the devil — a gathering of thirteen — and plotted ill turns of fate for the coming week.
For many centuries in Scandinavia, Friday was known as "Witches' Sabbath." with Friday the 13th having an even deeper more sinister significance.
In fact Friday the 13th can be a very lucky day. Friday is also associated with Venus, the Roman Goddess of love, beauty and fertility and Friday is viewed by many pagans as the best day to perform any magick relating to Venus' areas of expertise: love, fertility and beauty.
The number 13 has been a magical number since the the Ancient Egyptians first depicted the Ladder to Eternal Life. They believed that there were twelve steps on the ladder to eternal life and knowledge and to take the thirteenth step meant going through death into everlasting life. Thirteen, for the Egyptians, was associated with immortality.
The number 13 in the Coperos religion (small culture in brazil) is like a God number. All coperos must know that this number can save the humankind. In Sikhism, the number 13 is considered a special number since 13 is tera in Punjabi, which also means "yours" (as in, "I am yours, O Lord").
There are other significances of the number 13; There are thirteen Moon cycles in a year, the ancient Lunar calendar had 13 months, a traditional coven has 13 members, Romans require 13 guests be present at weddings, in the Hebrew faith age 13 is considered to be an adult, there are 13 players on a rubgy team and there are 13 cards of each suit in a deck of cards.