Numbers 21:21-26 New American Bible (Revised Edition) (NABRE)
Victory over Sihon. 21 Now Israel sent messengers to Sihon, king of the Amorites, with the message, 22 “Let us pass through your land. We will not turn aside into any field or vineyard, nor will we drink any well water, but we will go straight along the King’s Highway until we have passed through your territory.” 23 Sihon, however, would not permit Israel to pass through his territory, but mustered all his forces and advanced against Israel into the wilderness. When he reached Jahaz, he engaged Israel in battle. 24 But Israel put him to the sword, and took possession of his land from the Arnon to the Jabbok and as far as Jazer of the Ammonites, for Jazer is the boundary of the Ammonites. 25 Israel seized all the towns here, and Israel settled in all the towns of the Amorites, in Heshbon and all its dependencies. 26 For Heshbon was the city of Sihon, king of the Amorites, who had fought against the former king of Moab and had taken all his land from him as far as the Arnon.
Deuteronomy 2:26-36 New American Bible (Revised Edition) (NABRE)
26 So I sent messengers from the wilderness of Kedemoth to Sihon, king of Heshbon, with this offer of peace: 27 “Let me pass through your country. I will travel only on the road. I will not turn aside either to the right or to the left. 28 The food I eat you will sell me for money, and the water I drink, you will give me for money. Only let me march through, 29 as the descendants of Esau who dwell in Seir and the Moabites who dwell in Ar have done, until I cross the Jordan into the land the Lord, our God, is about to give us.” 30 But Sihon, king of Heshbon, refused to let us pass through his land, because the Lord, your God, made him stubborn in mind and obstinate in heart that he might deliver him into your power, as indeed he has now done.
31 Then the Lord said to me, Now that I have already begun to give over to you Sihon and his land, begin to take possession. 32 So Sihon and all his people advanced against us to join battle at Jahaz; 33 but since the Lord, our God, had given him over to us, we defeated him and his sons and all his people. 34 At that time we captured all his cities and put every city under the ban,[a] men, women and children; we left no survivor. 35 Our only plunder was the livestock and the spoils of the captured cities. 36 From Aroer on the edge of the Wadi Arnon and from the town in the wadi itself, as far as Gilead, no city was too well fortified for us. All of them the Lord, our God, gave over to us.