Deuteronomy 2:37

2:37 However, you did not approach the land of the Ammonites, the Wadi Jabbok, ¹  the cities of the hill country, or any place else forbidden by the Lord our God.

Deuteronomy 3:16

3:16 To the Reubenites and Gadites I allocated the territory extending from Gilead as far as Wadi Arnon (the exact middle of the wadi was a boundary) all the way to the Wadi Jabbok, the Ammonite border.

Joshua 12:2

12:2 King Sihon of the Amorites who lived ²  in Heshbon and ruled from Aroer (on the edge of the Arnon Valley) – including the city in the middle of the valley ³  and half of Gilead – all the way to the Jabbok Valley bordering Ammonite territory.

¹ sn Wadi Jabbok. Now known as the Zerqa River, this is a major tributary of the Jordan that normally served as a boundary between Ammon and Gad (Deut 3:16).

² tn Or perhaps, “reigned.”

³ tc The MT reads here, “and the middle of the valley,” but the reading “the city in the middle of valley” can be reconstructed on the basis of Josh 13:9, 16.