Deuteronomy 2:37

Of the river Jabbok, i.e. beyond Jabbok; for that was the border of the Ammonites, Joshua 12:2. Object. Half the land of the Ammonites is said to be given to the tribe of Gad, Joshua 13:25. Answ. This is true of that half of it which the Amorites had taken from them, but not of the other half, which yet was in the possession of the Ammonites. In the mountains; the mountainous country of the Ammonites. Forbad us, Heb. commanded us: commanding is put for forbidding here, as Genesis 2:16, Genesis 3:11 Leviticus 4:2 Deuteronomy 4:23. The words may be thus rendered, concerning which the Lord gave us command or charge, to wit, that we should not meddle with them, as was said before. So it is only an ellipsis of the preposition, which is very frequent.