1Gal 3:16; Rom 5:15–21; Isa 53:10–11

While the covenant of Works was made by God with Adam representing all mankind descending from him by natural generation, the covenant of Grace was made with the Lord Jesus Christ, representing His elect.

The parties in the two covenants may be tabulated as follows:

Our catechism calls the Lord Jesus Christ the second Adam not without reasons.

In the first place, the apostle Paul speaks of the Lord as the "last Adam":

• "The first man Adam was made a living soul; the last Adam was made a quickening spirit.… The first man is of the earth, earthy: the second man is the Lord from heaven" (1 Cor 15:45, 47).

In the second place Christ came to take the place of Adam as covenant representative to keep the covenant of Works and to pay for Adam’s transgression on behalf of those He would represent:

• "For as in Adam all die, even so in Christ shall all be made alive" (1 Cor 15:22);
• "As by the offence of one judgment came upon all men to condemnation; even so by the righteousness of one the free gift came upon all men unto justification of life. For as by one man’s disobedience many were made sinners, so by the obedience of one shall many be made righteous" (Rom 5:18-19).

Notice how the apostle Paul speak of Christ representing "all" when it is obvious that He does not represent all mankind, for if He represents all mankind, then all would be saved.

The apostle speaks of Christ representing "all" because he has in mind how Christ represented all He came to save just as Adam represented all his descendants by natural generation. Indeed, the Scripture makes this comparison even sharper by calling those whom Christ represents "His seed" (or "his descendents"):

Who are these seed of Christ? They are the "many" of Isaiah 53:11. They are those whom the Father had given unto Christ (Jn 17:9).

They are the sheep who would believe in the Lord (Jn 10:26). They are, in other words, the elect who have been chosen in Christ (Eph 1:4) and are therefore covenantally united to Him.

Take note that the covenant of Grace is not made with them individually as if faith is the meritorious condition of the covenant of Grace as sometimes taught. The covenant of Grace was made with Christ as our representative (cf. Gal 3:16), and the condition of the covenant is the same as that in the covenant of Works,—namely personal and perfect obedience to the law of God. Christ our representative fulfilled that condition. Faith is a gift procured by Christ for the elect (Eph 2:8) by which the elect is brought into lively union with him. Faith is not strictly speaking a condition of the covenant.

When was the covenant of Grace made? It was made in eternity, "before the foundation of the world" (Eph 1:4). This is why the Lord Jesus Christ is said to be "the Lamb slain from the foundation of the world" (Rev 13:8). The covenant of Grace was however revealed to man only after the Fall in the words of God: "And I will put enmity between thee and the woman, and between thy seed and her seed; it shall bruise thy head, and thou shalt bruise his heel" (Gen 3:15).

But Christ came only in the fullness of time (Eph 1:10; Gal 4:4). How then could the benefits of the covenant be enjoyed by anyone before the time? They could because the representative of the covenant is no ordinary man. He is the God-Man, who was eternally the Son of God, the second person of the Triune God, who is in very essence God. What God has determined to do, He will certainly do, and therefore it is in His sight as good as done.