Here, I. The Lord of hosts gives orders to Moses to make war upon the Midianites, and his commission no doubt justified this war, though it will not serve to justify the like without such commission. The Midianites were the posterity of Abraham by Keturah, Gen. 25:2. Some of them settled south of Canaan, among whom Jethro lived, and they retained the worship of the true God; but these were settled east of Canaan, and had fallen into idolatry, neighbours to, and in confederacy with, the Moabites. Their land was not designed to be given to Israel, nor would Israel have meddled with them if they had not made themselves obnoxious to their resentment by sending their bad women among them to draw them to whoredom and idolatry. This was the provocation, this was the quarrel. For this (says God) avenge Israel of the Midianites, Num. 31:2. 1. God would have the Midianites chastised, an inroad made upon that part of their country which lay next to the camp of Israel, and which was probably more concerned in that mischief than the Moabites, who therefore were let alone. God will have us to reckon those our worst enemies that draw us to sin, and to avoid them; and since every man is tempted when he is drawn aside of his own lusts, and these are the Midianites which ensnare us with their wiles, on them we should avenge ourselves, not only make no league with them, but make war upon them by living a life of mortification. God had taken vengeance on his own people for yielding to the Midianites’ temptations; now the Midianites, that gave the temptation, must be reckoned with, for the deceived and the deceiver are his (Job 12:16), both accountable to his tribunal; and, though judgment begin at the house of God, it shall not end there, 1 Pet. 4:17. There is a day coming when vengeance will be taken on those that have introduced errors and corruptions into the church, and the devil that deceived men will be cast into the lake of fire. Israel’s quarrel with Amalek, that fought against them, was not avenged till long after: but their quarrel with Midian, that debauched them, was speedily avenged, for they were looked upon as much more the dangerous and malicious enemies. 2. God would have it done by Moses, in his life-time, that he who had so deeply resented that injury might have the satisfaction of seeing it avenged. “See this execution done upon the enemies of God and Israel, and afterwards thou shalt be gathered to thy people.” This was the only piece of service of this kind that Moses must further do, and then he has accomplished, as a hireling, his day, and shall have his quietus—enter into rest: hitherto his usefulness must come, and no further; the wars of Canaan must be carried on by another hand. Note, God sometimes removes useful men when we think they can be ill spared; but this ought to satisfy us, that they are never removed till they have done the work which was appointed them.
II. Moses gives orders to the people to prepare for this expedition, Num. 31:3. He would not have the whole body of the camp to stir, but they must arm some of themselves to the war, such as were either most fit or most forward, and avenge the Lord of Midian. God said, Avenge Israel; Moses says, Avenge the Lord; for the interests of God and Israel are united, and the cause of both is one and the same. And if God, in what he does, shows himself jealous for the honour of Israel, surely Israel, in what they do, ought to show themselves jealous for the glory of God. Then only we can justify the avenging of ourselves when it is the vengeance of the Lord that we engage in. Nay, for this reason we are forbidden to avenge ourselves, because God has said, Vengeance is mine, I will repay.
III. A detachment is drawn out accordingly for this service, 1000 out of every tribe, 12,000 in all, a small number in comparison with what they could have sent, and it is probable small in comparison with the number of the enemies they were sent against. But God would teach them that it is all one to him to save by many or by few, 1 Sam. 14:6.
IV. Phinehas the son of Eleazar is sent along with them. It is strange that no mention is made of Joshua in this great action. If he was general of these forces, who do we not find him leading them out? If he tarried at home, why do we not find him meeting them with Moses at their return? It is probable, each tribe having a captain of its own thousand, there was no general, but they proceeded in the order of their march through the wilderness, Judah first, and the rest in their posts, under the command of their respective captains, spoken of Num. 31:48. But, the war being a holy war, Phinehas was their common head, not to supply the place of a general, but, by the oracle of God, to determine the resolves of their counsels of war, in which the captains of thousands would all acquiesce, and according to which they would act in conjunction. He therefore took with him the holy instruments or vessels, probably the breast-plate of judgment, by which God might he consulted in any emergency. Though he was not yet the high priest, yet he might be delegated pro hac vice—for this particular occasion, to bear the urim and thummim, as 1 Sam. 23:6. And there was a particular reason for sending Phinehas to preside in this expedition; he has already signalized himself for his zeal against the Midianites and their cursed arts to ensnare Israel when he slew Cozbi, a daughter of a chief house in Midian, for her impudence in the matter of Peor, Num. 25:15. He that had so well used the sword of justice against a particular criminal was best qualified to guide the sword of war against the whole nation. Thou hast been faithful over a few things, I will make thee ruler over many things.