Here, 1. Moses settles this matter with Eleazar, and with Joshua who was to be his successor, knowing that he himself must not live to see it perfected, Numbers 32:28-32:30. He gives them an estate upon condition, leaving it to Joshua, if they fulfilled the condition, to declare the estate absolute: “If they will not go over with you,” he does not say “you shall give them no inheritance at all,” but “you shall not give them this inheritance which they covet. If their militia will not come over with you, compel the whole tribes to come over, and let them take their lot with their brethren, and fare as they fare; they shall have possessions in Canaan, and let them not expect that the lot will favour them.” Hereupon they repeat their promise to adhere to their brethren, Numbers 32:31, 32:32. 2. Moses settles them in the land they desired. He gave it to them for a possession, Numbers 32:33. Here is the first mention of the half tribe of Manasseh coming in with them for a share; probably they had not joined with them in the petition, but, the land when it came to be apportioned proving to be too much for them, this half tribe had a lot among them, perhaps at their request, or by divine direction, or because they had signalized themselves in the conquest of this country: for the children of Machir, a stout and warlike family, had taken Gilead and dispossessed the Amorites, Numbers 32:39. “Let them win it and wear it, get it and take it.” And, they being celebrated for their courage and bravery, it was for the common safety to put them in this frontier-country. Concerning the settlement of these tribes observe, (1.) They built the cities, that is, repaired them, because either they had been damaged by the war or the Amorites had suffered them to go to decay. (2.) They changed the names of them (Numbers 32:38), either to show their authority, that the change of the names might signify the change of their owners, or because their names were idolatrous, and carried in them a respect to the dunghill-deities that were there worshipped. Nebo and Baal were names of their gods, which they were forbidden to make mention of (Exodus 23:13), and which, by changing the names of these cities, they endeavoured to bury in oblivion; and God promises to take away the names of Baalim out of the mouths of his people, Hosea 2:17. MHBCC 150.11
Lastly, It is observable that, as these tribes were now first placed before the other tribes, so, long afterwards, they were displaced before the other tribes. We find that they were carried captive into Assyria some years before the other tribes, 2 Kings 15:29. Such a proportion does Providence sometimes observe in balancing prosperity and adversity; he sets the one over-against the other. MHBCC 150.12