We have here an account of the victories obtained by Israel over Sihon and Og, which must be distinctly considered, not only because they are here distinctly related, but because long afterwards the memorial of them is distinctly celebrated, and they are severally assigned as instances of everlasting mercy. He slew Sihon king of the Amorites, for his mercy endureth for ever, and Og the king of Bashan, for his mercy endureth for ever, Psa 136:19, Psa 136:20.

I.Israel sent a peaceable message to Sihon king of the Amorites (Num 21:21), but received an unpeaceable return, worse than that of the Edomites to the like message, Num 20:18, Num 20:20. For the Edomites only refused them a passage, and stood upon their own defence to keep them out; but Sihon went out with his forces against Israel in the wilderness, out of his own borders, without any provocation given him (Num 21:23), and so ran himself upon his own ruin. Jephtha intimates that he was prompted by his politics to do this (Jdg 11:20), Sihon trusted not Israel to pass through his coast; but his politics deceived him, for Moses says, God hardened his spirit and made his heart obstinate, that he might deliver him into the hand of Israel, Deu 2:30. The enemies of God's church are often infatuated in those very counsels which they think most wisely taken. Sihon's army was routed, and not only so, but all his country came into the possession of Israel, Num 21:24, Num 21:25. This seizure is justified, 1. Against the Amorites themselves, for they were the aggressors, and provoked the Israelites to battle; and yet, perhaps, that would not have been sufficient to entitle Israel to their land, but that God himself, the King of nations, the Lord of the whole earth, had given them a grant of it. The Amorites formed one of the devoted nations whose land God had promised to Abraham and his seed, which promise should be performed when the iniquity of the Amorites should be full, Gen 15:16. Jephtha insists upon this grant as their title, Jdg 11:23, Jdg 11:24. The victory which God gave them over the Amorites put them in possession, and then, the promise made to their fathers having given them a right, by virtue of that they kept possession. 2. Against the Moabites, who had formerly been the lords-proprietors of this country. If they should ever lay claim to it, and should plead that God himself had provided that none of their land should be given to Israel for a possession (Deu 2:9), Moses here furnishes posterity with a replication to their plea, and Jephtha makes use of it against the Amorites 260 years afterwards, when Israel's title to this country was questioned. (1.) The justification itself is that though it was true this country had belonged to the Moabites, yet the Amorites had taken it from them some time before, and were now in full and quiet possession of it, Num 21:26. The Israelites did not take it out of the hands of the Moabites, they had before lost it to the Amorites, and were constrained to give up their pretensions to it; and, when Israel had taken it from the Amorites, they were under no obligation to restore it to the Moabites, whose title to it was long since extinguished. See here the uncertainty of worldly possessions, how often they change their owners, and how soon we may be deprived of them, even when we think ourselves most sure of them; they make themselves wings. It is our wisdom therefore to secure the good part which cannot be taken away from us. See also the wisdom of the divine Providence and its perfect foresight, by which preparation is made long before for the accomplishment of all God's purposes in their season. This country being designed in due time for Israel, it is beforehand put into the hand of the Amorites, who little think that they have it but as trustees till Israel come of age, and then must surrender it. We understand not the vast reaches of Providence, but known unto God are all his works, as appears in this instance, that he set the bounds of the people according to the number of the children of Israel, Deu 32:8. All that land which he intended for his chosen people he put into the possession of the devoted nations, that were to be driven out. (2.) For proof of the allegation, he refers to the authentic records of the country, for so their proverbs or songs were, one of which he quotes some passages out of (Num 21:27-30), which sufficiently proves what is vouched for, namely, [1.] That such and such places that are here named, though they had been in the possession of the Moabites, had by right of war become the dominion of Sihon king of the Amorites. Heshbon had become his city, and he obtained such a quiet possession of it that it was built and prepared for him (Num 21:27), and the country to Dibon and Nophah was likewise subdued, and annexed to the kingdom of the Amorites, Num 21:30, [2.] That the Moabites were utterly disabled ever to regain the possession. Even Ar of Moab, though not taken or attempted by Sihon, but still remaining the metropolis of Moab, yet was so wasted by this loss that is would never be able to make head, Num 21:28. The Moabites were undone, and even Chemosh their god had given them up, as unable to rescue them out of the hands of Sihon, Num 21:29. By all this it appears that the Moabites' claim to this country was barred for ever. There may be a further reason for inserting this Amorite poem, namely, to show that the triumphing of the wicked is short. Those that had conquered the Moabites, and insulted over them, were now themselves conquered and insulted over by the Israel of God. It is very probable that the same Sihon, king of the Amorites, that had got this country from the Moabites, now lost it to the Israelites; for, though it is said to be taken from a former king of Moab (Num 21:26), yet not by a former king of the Amorites; and then it shows how sometimes justice makes men to see the loss of that which they got by violence, and were puffed up with the gain of. They are exalted but for a little while, Job 24:24.

II.Og king of Bashan, instead of being warned by the fate of his neighbours to make peace with Israel, is instigated by it to make war with them, which proves in like manner to be his destruction. Og was also an Amorite, and therefore perhaps thought himself better able to deal with Israel than his neighbours were, and more likely to prevail, because of his own gigantic strength and stature, which Moses takes notice of, Deu 3:11, where he gives a more full account of this story. Here observe, 1. That the Amorite begins the war (Num 21:33): He went out to battle against Israel. His country was very rich and pleasant. Bashan was famous for the best timber (witness the oaks of Bashan), and the best breed of cattle, witness the bulls and kine of Bashan, and the lambs and rams of that country, which are celebrated, Deu 32:14. Wicked men do their utmost to secure themselves and their possessions against the judgments of God, but all in vain, when their day comes, on which they must fall. 2. That God interests himself in the cause, bids Israel not to fear this threatening force, and promises a complete victory: "I have delivered him into thy hand (Num 21:34); the thing is as good as done already, it is all thy own, enter and take possession." Giants are but worms before God's power. 3. That Israel is more than a conqueror, not only routs the enemies' army, but gains the enemies' country, which afterwards was part of the inheritance of the two tribes and a half that were first seated on the other side Jordan. God gave Israel these successes, while Moses was yet with them, both for his comfort (that he might see the beginning of that glorious work, which he must not live to see the finishing of) and for the encouragement of the people in the war of Canaan under Joshua. Though this was to them in comparison but as the day of small things, yet it was an earnest of great things.

For there is a fire gone out of Heshbon,.... Not before, but after Sihon had subdued it, as Jarchi observes; and is to be understood of his soldiers going out from thence, and making desolations in the adjacent parts, like a strong fire, and the fierce flames of it there is no resisting; and so the Jerusalem Targum,"for a people mighty, and burning like fire, are gone out of Heshbon:''see Amo 1:4, a flame from the city of Sihon: which is the same thing in other words, the city of Sihon being Heshbon, and a flame the same with fire; warriors, as both the Targums of Oakelos and Jerusalem interpret it; this seems to be what those composers undertook in their poetical way to foretell would be the case in future times; concluding, from the conquests already made, that they would be extended much further, and that no opposition could hinder:

it hath consumed Ar of Moab; the metropolis of the country of Moab, that is, they were as sure of it, and endeavoured to make the people by these their compositions as confident of it, that this city would fall into the hands of their armies, and be destroyed, as if it was already done; otherwise it does not appear that it ever was taken out of the hands of the Moabites, until taken by the Assyrians or Chaldeans; of this city See Gill on Isa 15:1.

and the lords of the high places of Arnon; who had the government of the high, strong, and fortified places all along the river Arnon; these it is suggested would be conquered by the Amorites; all the three Targums interpret it of the priests and worshippers in the temples, and at the altars of the idols in Arnon; and it may be rendered, "the Baals of the high places of Arnon", as if the gods of those places should fall into the victors' hands; and which seems to have some confirmation from what follows; and it may be observed, that in these parts there were some places called Bamoth Baal, or the high places of Baal, see Num 22:41, and Beth Baal Meon, which has its name from its being the temple and habitation of Baal, Jos 13:17.

Israel dwelt in all the cities--after exterminating the inhabitants who had been previously doomed (Deu 2:34).