91 "Hear, O Israel: You are to cross over the Jordan today, and go in to dispossess nations greater and mightier than yourself, cities great and fortified up to heaven, 2 a people great and tall, the descendants of the Anakim, whom you know, and of whom you heard it said, 'Who can stand before the descendants of Anak?' 3 Therefore understand today that the Lord your God is He who goes over before you as a consuming fire. He will destroy them and bring them down before you; so you shall drive them out and destroy them quickly, as the Lord has said to you. 4 Do not think in your heart, after the Lord your God has cast them out before you, saying, 'Because of my righteousness the Lord has brought me in to possess this land'; but it is because of the wickedness of these nations that the Lord is driving them out from before you. 5 It is not because of your righteousness or the uprightness of your heart that you go in to possess their land, but because of the wickedness of these nations that the Lord your God drives them out from before you, and that He may fulfill the word which the Lord swore to your fathers, to Abraham, Isaac, and Jacob.
6 Therefore understand that the Lord your God is not giving you this good land to possess because of your righteousness, for you are a stiff-necked people.
Matthew Henry's Commentary on Deuteronomy 9:1-6
Commentary on Deuteronomy 9:1-6
(Read Deuteronomy 9:1-6)
Moses represents the strength of the enemies they were now to encounter. This was to drive them to God, and engage their hope in him. He assures them of victory, by the presence of God with them. He cautions them not to have the least thought of their own righteousness, as if that procured this favour at God's hand. In Christ we have both righteousness and strength; in Him we must glory, not in ourselves, nor in any sufficiency of our own. It is for the wickedness of these nations that God drives them out. All whom God rejects, are rejected for their own wickedness; but none whom he accepts are accepted for their own righteousness. Thus boasting is for ever done away: see Ephesians 2:9,11,12.