Crossing fingers to achieve your own good luck, or in a display of hopeful solidarity that things go well for someone else, is a widely recognized gesture. The finger-cross has a long history—and, originally, it was not a solo act.
There are two main theories regarding the origins of finger-crossing for luck. The first comes from a pre-Christian pagan belief in the powerful symbolism of a cross. The intersection was thought to mark a concentration of good spirits and served to anchor a wish until it could come true. The practice of wishing upon a cross in early European cultures evolved to a tradition in which a person crossed their index finger over someone else’s to express hope that a wish would come true. Eventually, wish-makers realized they could go it alone and impart the benefit of making a cross to support their wishes without another person’s participation. At first, this took the form of a person crossing their two index fingers. Eventually this gesture morphed into the one-handed practice we still use today.
The alternate explanation also stems from the early days of Christianity, when practitioners were frequently persecuted for their beliefs. To recognize their fellow Christians, people developed a series of hand gestures, one of which involved forming the ichthys, or fish symbol, by touching thumbs and crossing index fingers. The symbol represents an acrostic in which the Greek letters i, ch, th, y, and s are also the first letters in the phrase Iēsous Christos, Theou Yios, Sōtēr, which in English means “Jesus Christ, Son of God, Savior.” This theory doesn’t fully explain how luck initially became associated with the gesture, but it suggests that crossing one’s fingers imparted a blessing or hope for a wish or prayer.
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A version of this story was published in 2012; it has been updated for 2024.