Why Do We Say “Knock on Wood”? The Surprising History Behind a Common Habit

  The next time you say “knock on wood” to avoid bad luck, have you wondered where this habit came from?

The practice dates back to ancient Celtic tribes, who believed spirits lived in trees. Knocking on tree trunks was a way to seek protection or call on good spirits. Later, in Christian Europe, the habit was linked to sacred objects, like church doors or crosses, to avoid tempting fate.

Psychologists today suggest that knocking on wood gives us a small sense of control over unpredictable events. Even if the spirits are long gone, our brains still enjoy that tiny reassurance.

So next time you hear a friend say it, remember: a millennia-old ritual lives on in everyday life.