Ecclesiastes 10:1-3; Ecclesiastes 10:12-15
Dead flies cause the ointment of the apothecary to send forth a stinking savour: so doth a little folly him that is in reputation for wisdom and honour.
A wise man's heart is at his right hand; but a fool's heart at his left.
Yea also, when he that is a fool walketh by the way, his wisdom faileth him, and he saith to every one that he is a fool.
The words of a wise man's mouth are gracious; but the lips of a fool will swallow up himself.
The beginning of the words of his mouth is foolishness: and the end of his talk is mischievous madness.
A fool also is full of words: a man cannot tell what shall be; and what shall be after him, who can tell him?
The labour of the foolish wearieth every one of them, because he knoweth not how to go to the city.