I thought "devil" was a swear for a long time. I also thought that if you swore, worms would grow in your mouth(something my mom said). So that certainly stopped me from swearing! I believed this until I was 9.
A childhood belief about swearing

others believed things like this
- I used to believe that swearing was just saying, “I swear!”Anon
- I believed that linguini was made of tape worms and was scared to eat pasta for a long time!— Mojo!
- I believed that if I looked too long in the mirror admiring myself the Devil would appear.— Paul Elletson
- I always thought that the gummy worms were real worms that had been mummified— The Ice Cream Sandwich Monster
- I used to believe that if a dog stuck their tongue in your mouth, you would get worms no matter what.— ` [ A ] m a n d a .
- When I was five, I used to believe that worms grow into snakes.— Mz Dimple