Jahaz
Jahaz, also called Jahaza, Jahazah, and Jahzah, is a town on the Transjordanian plateau remembered for two things: as the open ground where Sihon king of the Amorites was defeated by Israel, and as a Levitical city assigned to Reuben that later passed back into Moabite hands.
The Field of Sihon's Defeat
The first appearance of Jahaz in Israel's story is martial. When Israel asks Sihon for safe passage and is refused, the engagement is joined at Jahaz: "And Sihon would not allow Israel to pass through his border: but Sihon gathered all his people together, and went out against Israel into the wilderness, and came to Jahaz; and he fought against Israel" (Nu 21:23).
Moses' own retelling on the plains of Moab fixes the place name in Israel's memory of the conquest: "Then Sihon came out against us, he and all his people, to battle at Jahaz" (De 2:32).
Generations later Jephthah recites the same campaign to the king of Ammon as proof that the Transjordan belongs to Israel by right of conquest, not by encroachment: "But Sihon didn't trust Israel to pass through his border; but Sihon gathered all his people together, and encamped in Jahaz, and fought against Israel" (Jud 11:20). Three witnesses, one battlefield — Numbers, Deuteronomy, and Judges all anchor the defeat of Sihon at this town.
A Levitical City in Reuben
When the Transjordan is parceled out, Jahaz falls inside Reuben's territory and is listed among the towns of the plateau: "and Jahaz, and Kedemoth, and Mephaath," (Jos 13:18). Within that allotment the town is given to the Levites — the same Reubenite holdings later furnish Bezer, Kedemoth, and Mephaath as the Merarite Levitical share of the Transjordan (Jos 21:36-37).
Lost to Moab Again
By the prophetic period Jahaz is once more a Moabite town, and its name surfaces in the oracles against Moab as a marker of how far the cry of disaster carries. Isaiah hears the alarm from Heshbon and Elealeh reaching all the way south-east to Jahaz: "And Heshbon cries out, and Elealeh; their voice is heard even to Jahaz: therefore the armed men of Moab cry aloud; his soul trembles inside him" (Isa 15:4).
Jeremiah's longer Moab oracle places Jahzah on the same plateau under the same judgment: "And judgment has come upon the plain country, on Holon, and on Jahzah, and on Mephaath," (Jer 48:21). The pairing of Jahzah with Mephaath in Jeremiah mirrors the original Reubenite list in Joshua, but the towns are now reckoned as part of Moab's territory rather than Israel's — the same country where Sihon was once defeated has changed hands again.