Numbers 22:21-25

²¹And Balaam rose up in the morning, and saddled his ass, and went with the princes of Moab.

²²And God was very angry because he went; and the angel of the Lord rose up to withstand him. Now he had mounted his ass, and his two servants were with him.

²³And when the ass saw the angel of God standing opposite in the way, and his sword drawn in his hand, then the ass turned aside out of the way, and went into the field; and Balaam struck the ass with his staff to direct her in the way.

²⁴And the angel of the Lord stood in the avenues of the vines, a fence being on this side and a fence on that.

²⁵And when the ass saw the angel of God, she thrust herself against the wall, and crushed Balaam's foot against the wall, and he struck her again.