Charles Ellicott Commentary Deuteronomy 29:13

"that he may establish thee this day unto himself for a people, and that he may be unto thee a God, as he spake unto thee, and as he sware unto thy fathers, to Abraham, to Isaac, and to Jacob." — Deuteronomy 29:13 (ASV)

That he may establish thee to day for a people unto himself. —It must be carefully observed that this is the aspect of the covenant which makes Jehovah responsible for the fulfillment of the whole. “He takes all this trouble for the sake of establishing you in His presence for a people” (Rashi). The people’s part, as described in this verse, is only to accept the position.

And thus the covenant of Deuteronomy 29:13 is brought into the closest similarity with that which is called the New Covenant in Jeremiah 31:31 and Hebrews 8:8; the form of which is, I will be to them a God, and they shall be to me a people. God undertakes for the people’s part of the covenant as well as His own. In Deuteronomy, the first half of the New Covenant appears here in Deuteronomy 29:13: that He may be unto thee a God. The second part appears in Deuteronomy 30:6-8: The Lord thy God will circumcise thy heart ... to love the Lord thy God.