BIT

Part of a bridle
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. (Psalm 32:99Be 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. (Psalm 32:9))
Behold, we put bits in the horses' mouths, that they may obey us; and we turn about their whole body. (James 3:33Behold, we put bits in the horses' mouths, that they may obey us; and we turn about their whole body. (James 3:3))