Numbers 22:20-22

That night God came to Balaam and said, “Since these men have come to summon you, go with them, but do only what I tell you.” Balaam got up in the morning, saddled his donkey and went with the Moabite officials. But God was very angry when he went, and the angel of the LORD stood in the road to oppose him. Balaam was riding on his donkey, and his two servants were with him.