There are several theories about the origination of the term; the origins, however, are not completely clear.
Theory 1: Knocking/touching wood called on the Gods for protection.
Some people in Europe and parts of Africa (territories that were a part of the Roman Empire) believed in worshiping multiple gods.
These people were called Pagans (in a derogatory sense), and they are said to have believed that spirits and gods resided in trees.
Knocking on the tree trunks was a way to rouse the spirits and call on their protection (of good luck).
But it could have also been a way of showing gratitude for a stroke of good luck.
Many Christians believe that they are referencing the wood from Christ’s crucifixion, so they call on Christ for protection or good fortune when they knock on wood.
Theory 2: It was done to chase away evil spirits.
This theory also attributes ‘knocking wood’ to the Pagans but states that instead of calling on the protection of Gods, they did this to chase away evil spirits.
When one spoke about current good luck or hope for future good luck, one knocked on the tree trunk to prevent the evil spirits from listening, thereby preventing the reversal of good luck.
Theory 3: 18th-century auctioneers touched wood on items they considered sold.
If you placed a bid on an item and the auctioneer touched wood on that item, it meant you won the bid and got the item; ‘Touchwood’, therefore, represents winning (good luck).
Theory 4: It comes from a children’s game called “Tiggy Touchwood”.
In this game, players were immune from being caught whenever they touched a piece of wood such as a tree or a door.
Since ‘touching wood’ brought protection, the phrase caught on because the game was very well-known among both kids and adults.
