12:2 Middle of the river - It is not unusual even among us, for a river to be divided between two lords, and for their territories or jurisdictions to meet in the middle of the river: and besides, here is a very particular reason for this expression, because the city Ar, which was no part of Sihon's dominions, but belonged to the Moabites, Deut 2:9,18, was in the middle of the river Arnon, Deut 2:36 3:16, and therefore the middle of the river is properly here mentioned, as the bound of Sihon's dominion on that side. Half Gilead - Heb. and the half Gilead, that is, half of the country of Gilead; this doth not denote the bound from which his dominion began, but the country, over which his dominion was, which began at Arnon, and took in half Gilead, and ended at Jabbok, beyond which was the other half of Gilead which belonged to Og.
12:1-6 Fresh mercies must not drown the remembrance of former mercies, nor must the glory of the present instruments of good to the church diminish the just honour of those who went before them, since God is the same who wrought by both. Moses gave to one part of Israel a very rich and fruitful country, but it was on the outside of Jordan. Joshua gave to all Israel the holy land, within Jordan. So the law has given to some few of God's spiritual Israel worldly blessings, earnests of good things to come; but our Lord Jesus, the true Joshua, provided for all the children of promise spiritual blessings, and the heavenly Canaan.
