The custom of crossing your fingers for good luck is fairly common. Superstition states that the act of crossing one's index and middle fingers brings good luck and wards off evil spirits or witches. While the origins of this gesture are somewhat murky, it is commonly believed that the sign originated from early Christianity or pre-Christianity. While there is no solid proof of any one theory, the prevalence of crossing your fingers in cultures with a Christian background lends some credence to the claim. This idea is further supported by noting that the gesture is not common among Muslim or Buddhist cultures.

The crossing of one's index and middle fingers is said to bring good luck and ward off evil spirits and witches.

Some historians contend that this gesture pre-dates Christianity and was an early European device. Those who believed in sacred geometry thought that benign spirits lived at the intersection of crosses. These believers would extend their index fingers to make wishes. One person held out his or her finger and made the wish. The second person responded by crossing the finger with his or her own, showing support for the idea and invoking the benign spirits.

It is a common belief that the act of crossing one's fingers originated from early Christianity.

The theory of a Christian origin of crossing your fingers is based on early periods in the religion's history. During these early times, Christianity was an outlawed religion and the disciples of Christ usually formed a secret society. To protect the identity of the sect's followers, secret hand signs were developed so the members could recognize each other.

When it began, the act of crossing fingers was probably a two person process. A Christian would extend his or her hand with the index finger and thumb forming an L shape and another Christian would do the same. When their thumbs were pressed together and index fingers crossed, this would form the shape of the Christian fish symbol. Over the years, the signs of the cross and fish came to stand for good luck and blessings, as well as Christianity.

While the process of crossing your fingers for luck may have been around for centuries, it required the actions of two people. Sometimes, an individual needs that extra luck when there isn't another person around, however. The evolution of the gesture was inevitable as people developed ways of crossing fingers — and commanding their fortunes — independently.

The modern version of crossing your fingers probably came into existence during the time of the Hundred Years War. In this epic war between France and England, which lasted from 1337 to 1457, the rival armies wanted all the luck they could muster. The archer preparing to make a shot would have crossed his fingers and then said a prayer before pulling the bowstring.