Numbers 22:21-24

So the next morning Balaam got up, saddled his donkey, and started off with the Moabite officials. But God was angry that Balaam was going, so he sent the angel of the LORD to stand in the road to block his way. As Balaam and two servants were riding along, Balaam’s donkey saw the angel of the LORD standing in the road with a drawn sword in his hand. The donkey bolted off the road into a field, but Balaam beat it and turned it back onto the road. Then the angel of the LORD stood at a place where the road narrowed between two vineyard walls.