Deuteronomy 2:16,17 - Joseph Benson’s Commentary on the Old and New Testaments

When all the men of war were consumed Israel is not called to march against and attack the Canaanites till the men most fit for war, and who probably had learned the art of it in Egypt, and had been used to hardship, were all wasted and dead from among the people, and only a host of new raised men, trained up in a wilderness, were left, in whom, as being possessed of little knowledge, experience, or natural fortitude, no great dependance could be placed. Thus it became more fully manifest that the excellency of the power which subdued the warlike Canaanites, was of God and not of man. On the same principle, and with the same design, long after this, were the following words spoken by the Lord to Gideon: The people that are with thee are too many for me to give the Midianites into their hands, lest Israel vaunt themselves against me, saying, Mine own hand hath saved me. And thus, to subdue the enemies of God's church, and bring sinners to the obedience of the faith, he hath chosen the weak things of the world, and things that are despised, and things that are not, to bring to naught the things that are, that no flesh may glory in his presence.