Numbers 23:12 in the King James Version
And he answered and said, Must I not take heed to speak that which the LORD hath put in my mouth?
Context
11 Balak said to Balaam, “What have you done to me? I took you to curse my enemies, and behold, you have blessed them altogether.”
12 He answered and said, “Must I not take heed to speak that which the LORD puts in my mouth?”
13 Balak said to him, “Please come with me to another place, where you may see them. You shall see just part of them, and shall not see them all. Curse them from there for me.”