John Gill Bible Commentary

But Sihon king of Heshbon would not let us pass by him,.... Or through his country, as was desired: for the Lord had hardened his spirit, and made his heart obstinate; as he did Pharaoh's, for whom he will he hardens; so that he would not listen to the proposals made to him, nor grant the requests asked of him, but with pride and haughtiness of spirit despised and disdained Israel: that he might deliver him into thine hand; that so an opportunity might offer of fighting with him, and taking his country from him; whereas, had he been peaceable and flexible, he had continued in the enjoyment of his land, and Israel would not have had that advantage against him; but God, who has the hearts of kings and of all men in his hands, so wrought upon him that he should take the steps he did, which made way for the delivery of him and his country into the hands of the Israelites: as appeareth this day: for when Moses made this speech, the kingdom of Sihon was possessed by the Israelites, Num 21:24.