Numbers 21:23-30

But Sihon would not let Israel pass through his territory. He mustered his entire army and marched out into the wilderness against Israel. When he reached Jahaz, he fought with Israel. Israel, however, put him to the sword and took over his land from the Arnon to the Jabbok, but only as far as the Ammonites, because their border was fortified. Israel captured all the cities of the Amorites and occupied them, including Heshbon and all its surrounding settlements. Heshbon was the city of Sihon king of the Amorites, who had fought against the former king of Moab and had taken from him all his land as far as the Arnon. That is why the poets say: “Come to Heshbon and let it be rebuilt; let Sihon’s city be restored. “Fire went out from Heshbon, a blaze from the city of Sihon. It consumed Ar of Moab, the citizens of Arnon’s heights. Woe to you, Moab! You are destroyed, people of Chemosh! He has given up his sons as fugitives and his daughters as captives to Sihon king of the Amorites. “But we have overthrown them; Heshbon’s dominion has been destroyed all the way to Dibon. We have demolished them as far as Nophah, which extends to Medeba.”