'Folly' in the Bible

He will die for lack of discipline, and he goes astray because of his great folly.

Every sensible person acts from knowledge, but a fool demonstrates folly.

The naive inherit folly, but the careful are crowned with knowledge.

To devise folly is sin, and people detest a scoffer.

A dog that returns to its vomit is like a fool who reverts to his folly.