Verses with the word fool's in the Old Testament (7 verses):

Proverbs 12:16
A fool's wrath is presently known: but a prudent man covereth shame.

Proverbs 18:6
A fool's lips enter into contention, and his mouth calleth for strokes.

Proverbs 18:7
A fool's mouth is his destruction, and his lips are the snare of his soul.

Proverbs 26:3
A whip for the horse, a bridle for the ass, and a rod for the fool's back.

Proverbs 27:3
A stone is heavy, and the sand weighty; but a fool's wrath is heavier than them both.

Ecclesiastes 5:3
For a dream cometh through the multitude of business; and a fool's voice is known by multitude of words.

Ecclesiastes 10:2
A wise man's heart is at his right hand; but a fool's heart at his left.