Numbers 21
26 For Heshbon was the town of Sihon, king of the Amorites, who had made war against an earlier king of Moab and taken from him all his land as far as the Arnon.
27 Ref So the makers of wise sayings say, Come to Heshbon, building up the town of Sihon and making it strong:
28 Ref For a fire has gone out of Heshbon, a flame from the town of Sihon: for the destruction of Ar in Moab, and the lords of the high places of the Arnon.