This is leading to a main point in my review of Coffey. I am indebted to Drake Shelton for his hard and thorough work on this.
Samuel Rutherford had earlier proposed a more traditional view that the eternal Covenant is called the Covenant of Redemption as is made between the Father and the Son. This is distinct from the Covenant of Grace which is made between God and all those who profess faith. The promises of the covenants are different. To Christ it was promised, upon supplying the condition of the terms of the Covenant of Redemption, to be rewarded by being seated at God’s right hand, to rule over the whole world, to have a an elect seed and be the mediator of his people. These rewards are not promised to those in the Covenant of Grace. The promises to those in the Covenant of Grace include the remission of sins, being accounted righteous in Christ, the adoption as sons, a new nature, and holiness among others. These are not promises that Christ received. It was because Christ’s humanity was NOT “the form of man’s redemption” that the COR was distinct from the COG. Samuel Rutherford says,
“Whosoever receives in his body the Seals of the Covenant of Grace, Circumcision, and Baptism, and yet needs no putting off the body of the sins of the flesh, by Circumcision, and needs no forgiveness of sin, no regeneration, no burying with Christ in Baptism, as Colossians 2:11 , 12; Romans 6:3-5, and eats the Passover, and needs not that the Lamb of God take away his sins, as John 1:29 since he is holy, and without sin, he must be under the Covenant, and God must be his God, in some other Covenant than sinners are…Christ must have received Seals for other uses and ends, then sinners received them” (Covenant of Life Opened, pg. 418)
If one affirms that Christ is in the same COG as sinners, he cannot escape from Robinson’s argument that this is an ipso facto admission that Christ is a Son of God by adoption as believers are, and not by nature…
Rutherford says of the Covenant of Redemption,
“it is an eternal transaction and compact between Jehovah and the second Person the Son of God, who gave personal consent that he should be the Undertaker, and no other…Christ is predestinate the head, the firstborn of the house, and of the many brethren, and say Amen to the choice, and we are chosen in him, as our head, and he was foreordained the Mediator, and the Lamb before the foundation of the world was laid, to be slain for our sin.” (pg. 429-430)
The Sum of Saving Knowledge states,
“2b The sum of the Covenant of Redemption is this: God having freely chosen to life a certain number of lost mankind, for the glory of his rich grace, did give them, before the world began, to God the Son, appointed Redeemer, that, upon condition he would humble himself so far as to assume the human nature, of a soul and a body, to personal union with his divine nature, and submit himself to the law, as surety for them, and satisfy justice for them, by giving obedience in their name, even to the suffering of the cursed death of the cross, he should ransom and redeem them all from sin and death, and purchase to them righteousness and eternal life, with all saving graces leading there to, to be effectually, by means of his own appointment, applied in due time to every one of them. This condition the Son of God (who is Jesus Christ our Lord) did accept before the world began, and in the fulness of time came into the world, was born of the Virgin Mary, subjected himself to the law, and completely paid the ransom on the cross: But by virtue of the foresaid bargain, made before the world began, he is in all ages, since the fall of Adam, still upon the work of applying actually the purchased benefits of the elect; and that he does by way of entertaining a covenant of free grace and reconciliation with them, through faith in himself; by which covenant, he makes over to every believer a right and interest to himself, and to all his blessings”
Here Rutherford and the Sum of Saving Knowledge affirm clearly that the same Eternal Person who authored the COR is the same Person who suffered on the cross. This person was not a product of the union between human and divine but was an Eternal Person who assumed a human nature. This was the point that convinced me of the hypostatic union a year ago.
So what does it mean to be united to Christ? First, it means that Christ represents you in the Covenant of Redemption. This is a Representational Union. See Samuel Rutherford, Covenant and Life Opened and my article concerning it here. Second, it means that the Ideas in the Logos are directly and univocally impressed upon the mind of a man. Isa 53:11 By His knowledge the Righteous One, My Servant, will justify the many. These Ideas are not just general propositions that all men receive but the propositions of special revelation written upon the heart. No doubt the Scholastic and the Easterner will flip the script when they read this so I have provided articles here and here in reply regarding the Logos and Saving Faith.