By him, i.e. by his borders. Obstinate; unmovable and inexorable to our desires.
Related Commentaries of Deuteronomy 2:30
Deuteronomy 2:30
30 But Sihon king of Heshbon would not let us pass by him: for the LORD thy God hardened his spirit, and made his heart obstinate, that he might deliver him into thy hand, as appeareth this day.