There is a popular superstition where people would knock on any wooden material to wish away misfortunes. The person says the words “knock on wood” while knocking on a wooden wall or any wooden surfaces, then proceeds to wish off the troubling misfortune they have in mind. What these people, who practice this superstition, don’t know is that this originated from an occult in ancient Celtic cultures. Faithful Catholics are advised not to do this.
This “Knock on wood” practice were usually done by the Druids who were the religious leaders of the ancient Celtics. They believe that spirits lives in the trees of the forest and when you knock on wood, you’re asking the spirit that lives in that wood to come to your aid and grant your requests.
From an ordinary person’s perspective, this might seem juvenile and something that doesn’t need to be taken seriously. But we often don’t realize how the occult can influence our day-to-day lives and how being passive about these superstitions can contribute to our falling out of grace. These kinds of acts are forms of idolatry that violates God’s first commandment. Nothing should ever replace God in our lives nor should we seek assistance from unknown spirits. Even if it’s just for fun.
Deuteronomy 18:10-13 (NABRE) states:
"Let there not be found among you anyone who causes their son or daughter to pass through the fire, or practices divination, or is a soothsayer, augur, or sorcerer, or who casts spells, consults ghosts and spirits, or seeks oracles from the dead. Anyone who does such things is an abomination to the LORD, and because of such abominations the LORD, your God, is dispossessing them before you. You must be altogether sincere with the LORD, your God."
This scripture reminds us that we ought to be sincere towards God. Consulting to spirits or even just acting out superstitions shows our lack of respect and confidence to God and therefore is considered as an abomination.
Leviticus 19:31 (NABRE) reads:
"Do not turn to ghosts or consult spirits, by which you will be defiled. I, the LORD, am your God."
The Lord himself, our God, strongly advises us not to talk to ghosts and unknown spirits. Doing so defiles our very being.
We need to realize that we can not use the powers of evil for our own benefits. It is the devil who uses us and not the other way around. Conversations and asking for favors from unknown spirits is considered as a mortal sin in the Catholic Church and must always be avoided by the faithful.