10 When you come up against a city to attack it, call out, "Peace?" 11 If they answer, "Yes, peace!" and open the city to you, then everyone found there will be conscripted as forced laborers and work for you. 12 But if they don't settle for peace and insist on war, then go ahead and attack. 13 God, your God, will give them to you. Kill all the men with your swords. 14 But don't kill the women and children and animals. Everything inside the town you can take as plunder for you to use and eat - God, your God, gives it to you. 15 This is the way you deal with the distant towns, the towns that don't belong to the nations at hand. 16 But with the towns of the people that God, your God, is giving you as an inheritance, it's different: don't leave anyone alive. 17 Consign them to holy destruction: the Hittites, Amorites, Canaanites, Perizzites, Hivites, and Jebusites, obeying the command of God, your God. 18 This is so there won't be any of them left to teach you to practice the abominations that they engage in with their gods and you end up sinning against God, your God.
Matthew Henry's Commentary on Deuteronomy 20:10-18
Commentary on Deuteronomy 20:10-12
(Read Deuteronomy 20:10-12)
The Israelites are here directed about the nations on whom they made war. Let this show God's grace in dealing with sinners. He proclaims peace, and beseeches them to be reconciled. Let it also show us our duty in dealing with our brethren. Whoever are for war, we must be for peace. Of the cities given to Israel, none of their inhabitants must be left. Since it could not be expected that they should be cured of their idolatry, they would hurt Israel. These regulations are not the rules of our conduct, but Christ's law of love. The horrors of war must fill the feeling heart with anguish upon every recollection; and are proofs of the wickedness of man, the power of Satan, and the just vengeance of God, who thus scourges a guilty world. But how dreadful their case who are engaged in unequal conflict with their Maker, who will not submit to render him the easy tribute of worship and praise! Certain ruin awaits them. Let neither the number nor the power of the enemies of our souls dismay us; nor let even our own weakness cause us to tremble or to faint. The Lord will save us; but in this war let none engage whose hearts are fond of the world, or afraid of the cross and the conflict. Care is here taken that in besieging cities the fruit-trees should not be destroyed. God is a better friend to man than he is to himself; and God's law consults our interests and comforts; while our own appetites and passions, which we indulge, are enemies to our welfare. Many of the Divine precepts restrain us from destroying that which is for our life and food. The Jews understand this as forbidding all wilful waste upon any account whatsoever. Every creature of God is good; as nothing is to be refused, so nothing is to be abused. We may live to want what we carelessly waste.