(2) Only that the generations of the children of Israel might know, to teach them war.--The LXX. here render, "Only because of the generations of the children of Israel to teach them war." The Vulgate is here a mere paraphrase, and the translations vary. The meaning seems to be, "Only that He (Jehovah) might know the generations of the children of Israel, to teach them war." The expression resembles 2Chronicles 32:31. The "teaching them war" doubtless implies the lesson that they could only learn successfully by the help of God.

As before knew nothing thereof.--That is, "knew nothing of those nations, or of those wars."

3:1-7 As the Israelites were a type of the church on earth, they were not to be idle and slothful. The Lord was pleased to try them by the remains of the devoted nations they spared. Temptations and trials detect the wickedness of the hearts of sinners; and strengthen he graces of believers in their daily conflict with Satan, sin, and this evil world. They must live in this world, but they are not of it, and are forbidden to conform to it. This marks the difference between the followers of Christ and mere professors. The friendship of the world is more fatal than its enmity; the latter can only kill the body, but the former murders many precious souls.Only that the generations of the children of Israel might know and teach them war,.... That is, the following nations were left in the land, that the young generations of Israel might by their wars and conflicts with them learn the art of war, and be inured to martial discipline; which, if none had been left to engage with, they had been ignorant of: besides, their fathers in Joshua's time, as Jarchi and Kimchi observe, had no need to learn the art of war, for God fought for them; they did not get possession of the land by their own arm, and by their sword, but by the power of God in a miraculous way; but now this was not to be expected, and the Canaanites were left among them to expel, that they might be trained up in the knowledge of warlike affairs, and so be also capable of teaching their children the military art; which they should make use of in obeying the command of God, by driving out the remains of the Canaanites, and not give themselves up to sloth and indolence; though some think that the meaning is, that God left these nations among them, that they might know what war was, and the sad effects of it; and the difference of fighting with their enemies alone, as other men, and the Lord fighting along with them, and for them, as he did for their fathers:

at least such as before knew nothing thereof; being either unborn, or at an age incapable of bearing arms, or learning the art of war.