17:7 And I will establish my covenant - Not to be altered or revoked; not with thee only, then it would die with thee but with thy seed after thee; and it is not only thy seed after the flesh, but thy spiritual seed. It is everlasting in the evangelical meaning of it. The covenant of grace is everlasting; it is from everlasting in the counsels of it, and to everlasting in the consequences of it; and the external administration of it is transmitted, with the seal of it, to the seed of believers, and the internal administration of it by the Spirit to Christ's seed in every age. This is a covenant of exceeding great and precious promises. Here are two which indeed are all - sufficient, that God would be their God. All the privileges of the covenant, all its joys, and all its hopes, are summed up in this. A man needs desire no more than this to make him happy. What God is himself, that he will be to his people: wisdom to guide and counsel them, power to protect and support them, goodness to supply and comfort them; what faithful worshippers can expect from the God they serve, believers shall find in God as theirs. This is enough, yet not all.
17:7-14 The covenant of grace is from everlasting in the counsels of it, and to everlasting in the consequences of it. The token of the covenant was circumcision. It is here said to be the covenant which Abraham and his seed must keep. Those who will have the Lord to be to them a God, must resolve to be to him a people. Not only Abraham and Isaac, and his posterity by Isaac, were to be circumcised, but also Ishmael and the bond-servants. It sealed not only the covenant of the land of Canaan to Isaac's posterity, but of heaven, through Christ, to the whole church of God. The outward sign is for the visible church; the inward seal of the Spirit is peculiar to those whom God knows to be believers, and he alone can know them. The religious observance of this institution was required, under a very severe penalty. It is dangerous to make light of Divine institutions, and to live in the neglect of them. The covenant in question was one that involved great blessings for the world in all future ages. Even the blessedness of Abraham himself, and all the rewards conferred upon him, were for Christ's sake. Abraham was justified, as we have seen, not by his own righteousness, but by faith in the promised Messiah.
