For years now I have wondered where all of my mother's interesting superstitions originated. She always seemed to believe in them, and a few sayings I find myself saying from time to time.
The phrase I use the most is "knock on wood." Usually one would only say this [while knocking on wood] after they had professed some stroke of good luck.
Long ago, it was believed that to touch wood or knock on wood helped ward off evil consequences or bad luck because of a recent action one had taken to an untimely boast about good fortune; it can also be a charm to bring good luck. The origin of "knock on or touch wood" is unknown, but some think it pre-dates Christianity. There is an old Irish belief that if one knocks on wood it would let the little people know that you are thinking of them for a bit of good luck.
Mom would never walk under a ladder and would caution anyone else to avoid it too. This superstition of bad luck is widespread in America and Europe. One theory of its origin is that a ladder leaning against a wall forms a triangle or trinity with the ground. Walking through this triangle is disrespectful to God or in other words could represent removing yourself from the Savior. Whatever the origin of this superstition, we really should not walk under ladders if only for safety sake.
A whole day could be ruined for mom if she saw a black cat walk on her path. Many people in the middle ages believed that black cats were associated with evil because cats are nocturnal, and they roam about at night.
Now the tragedy of a broken mirror would have longer lasting effects--seven years of bad luck. Some believe that the mirror is a reflection of the soul. If one should break a mirror, then the soul would also be broken. But the soul is said to regenerate every seven years and come back unbroken. [What does the soul do for the seven years?]
Tradition true or false can be passed down for many generations, and as we can see in our family probably hundreds of years. Maybe we need to ask ourselves, "Are these ways of thinking something we want to pass down to our posterity?" Because of me, my children will probably say for years to come when they run into good luck, "knock on wood" so that it will last. I know I say these things while never thinking what it really means.