I will establish my covenant between me and thee, and thy seed after thee, in their generations, for an everlasting covenant, to be a God to thee, and to thy seed after thee. — Genesis 17:7
GOD having framed man an understanding creature, hath made him fit to have communion and intercourse with himself; because he can by his understanding discern that there is a better good out of himself, in communion and fellowship with which, happiness consists. Other creatures—wanting understanding to discern a better good out of than in themselves, their life being their good—desire only the continuance of their own being, without society and fellowship with others. But man, having the knowledge of God, the Creator of heaven and earth, but especially of God the Redeemer, providing for him a second being better than his first, understandeth that his best and chiefest good dependeth more in him than in himself; and because his happiness standeth in acquaintance and fellowship with this God, which is the chief good, he desireth a communion with him, that he may partake of his good.
This communion and fellowship of man with God, was first founded on a covenant of works made with Adam in paradise. If he did obey, and did not eat of the forbidden fruit, he should have life both for himself and his posterity; the which covenant, because God would not have forgotten, he afterward renewed in the delivery of the ten commandments, requiring from man obedience to them in his own person, exactly, at all times, perpetually: promising life on the obedience, and threatening death and cursing if he continued not in everything the law required to do. But this fellowship being placed in man’s own freedom, and having so weak a foundation, he lost both himself and it, so that now by the first covenant of works, Adam and all his posterity are under a curse; for we cannot fulfil the law that requireth personal obedience, perfect obedience, and exact obedience. He that ‘continueth not in all is cursed,’ Gal. 3:10. The law then findeth us dead and killeth us. It findeth us dead before, and not only leaves us dead still, but makes us more dead.
Now after this fall, man’s happiness was to recover again his communion and fellowship with God; and therefore we must have a new covenant before we can have life and comfort. God must enter into new conditions with us before we can have any communion with him.
God therefore, loving man, doth after the breach of the first agreement and covenant, when Adam had lost himself by his sin, and was in a most miserable plight as ever creature was in the world, falling from so great a happiness into wondrous misery; he raised him up and comforted him by establishing a second, a new and better covenant, laying the foundation of it in the blessed seed of the woman, Christ the Messiah, who is the ground of this new covenant, and so of our communion and fellowship with God, without whom there can be no intercourse between God and us in love. And because this covenant was almost forgotten, therefore now in Abraham’s time God renewed it to Abraham in this place: ‘I will be thy God, and the God of thy seed after thee,’ &c.
There are four periods of time of renewing this covenant: first, from Adam to Abraham; and in those first times of the world, those that were under the covenant were called the ‘sons and daughters of God,’ ‘the children of the promise,’ and the covenant of grace was called a promise of the blessed seed.
Secondly, From Abraham to Moses; and then it was called a covenant, and they the children of the covenant. ‘I will establish my covenant’. A covenant is more than a promise, and a more solemn thing, because there be ceremonies.
The third period of renewing the covenant of grace was from Moses to Christ; and then it was more clear, whenas to the covenant made with Abraham, who was sealed with the sacrament of circumcision, the sacrament of the paschal lamb was added, and all the sacrifices Levitical; and then it was called a testament. That differeth a little from a covenant; for a testament is established by blood, it is established by death. So was that; but it was only with the blood and death of cattle sacrificed as a type.