Psalm 32:9
"Be ye not as the horse, or as the mule, which have no understanding: whose mouth must be held in with bit and bridle, lest they come near unto thee."
Cross References (ranked by relevance)
A whip for the horse, a bridle for the ass, and a rod for the fool’s back.
For my people is foolish, they have not known me; they are sottish children, and they have none understanding: they are wise to do evil, but to do good they have no knowledge.
Behold, we put bits in the horses’ mouths, that they may obey us; and we turn about their whole body.
Who teacheth us more than the beasts of the earth, and maketh us wiser than the fowls of heaven?
I have surely heard Ephraim bemoaning himself thus; Thou hast chastised me, and I was chastised, as a bullock unaccustomed to the yoke: turn thou me, and I shall be turned; for thou art the LORD my God.