John Calvin Commentary Numbers 23:17

"And he came to him, and, lo, he was standing by his burnt-offering, and the princes of Moab with him. And Balak said unto him, What hath Jehovah spoken?" — Numbers 23:17 (ASV)

And when he came to him. Balak inquires what God had answered, although he had rejected the previous revelation. Thus do hypocrites profess anxious concern when inquiring about God's will, while the knowledge of it is intolerable to them. Therefore, their extreme earnestness in inquiry is nothing but mere pretense.

Besides, Balak hunts, as it were, for God's answer through distant divination, while a testimony to God’s will was all the time engraved upon his heart. But this is the just punishment for perverse curiosity, when the wicked attempt to impose a law upon God, that He may submit to their wishes. Balak omits nothing regarding outward ceremonies; he humbly attends at the altars for the purpose of propitiating God. Yet, in the meantime, he would have God be obedient to himself, and cannot endure to listen to God, unless God speaks to him in flattering and deceptive terms.