May I put the knife by the bed?

You can defend yourself. If a thief breaks into the house, you have a self-defense weapon! There are many knives in the hidden place beside my father's bed!

Me! Influenced by my dad, I put a thick stainless steel tube for self-defense!

Superstition is:

Knives can ward off evil spirits!

If you want to keep the ghost out of the room, put a knife in the door, with the knife facing the door, or a barbed harpoon.

If there is a ghost in the house, knock hard with the back of the knife, and the ghost will run away in fear!