Reader Dante wrote in to ask, “Why is knocking on wood good luck?”
Traditionally, when you speak of your own good fortune, you follow up with a quick knock on a piece of wood to keep your luck from going bad. More recently, simply saying the phrase “knock on wood”—or “touch wood” in the UK—has replaced actually knocking. Where’d all this come from?
Before Christianity and Islam came around to spoil the party with their rules about idolatry, many pagan groups and other cultures—from Ireland to India to elsewhere in the world—worshipped or mythologized trees. Some peoples used trees as oracles, some incorporated them into worship rituals and some, like the ancient Celts, regarded them as the homes of certain spirits and gods.
Authors Stefan Bechtel and Deborah Aaronson both suggest two connections between knocking on wood and these spirits in their respective books, The Good Luck Book and Luck: The Essential Guide.
The first possible origin of knocking on wood is that it's a much more laid-back version of the ruckus that pagan Europeans raised to chase away evil spirits from their homes and trees or to prevent them from hearing about, and ruining, a person’s good luck.
The other origin they suggest is that some of these tree worshippers laid their hands on a tree when asking for favor from the spirits/gods that lived inside it, or did it after a run of good luck as a show of gratitude to the supernatural powers. Over the centuries, the religious rite may have morphed into the superstitious knock that acknowledges luck and keeps it going.
“In either case, you are seeking protection against envy and anger,” Bechtel and co-author Laurence R. Stains* write. “The envy of evil spirits and the anger of the gods, who take a dim view on mortals bearing too much pride and who get especially annoyed when they're responsible for your run of good luck and you're not grateful.”
*Mentalfloss.com deputy editor Erin and I both took journalism classes with Larry in college, but I didn’t know he’d written this book until I started working on this post. Small world, huh?