Numbers 21:22-23

22“Let me pass through your land; we will not turn away [from the road] into field or vineyard; we will not drink the water of the wells. We will go by the king’s highway until we have crossed your border.”

23But Sihon would not allow Israel to pass through his border. Instead Sihon gathered all his people together and went out against Israel into the wilderness, and came to Jahaz, and he fought against Israel.