John Calvin Commentary Romans 6:5

"For if we have become united with [him] in the likeness of his death, we shall be also [in the likeness] of his resurrection;" — Romans 6:5 (ASV)

For if we have been ingrafted, etc. He strengthens in plainer words the argument he has already stated. The analogy he mentions now leaves nothing doubtful, since grafting signifies not only a correspondence of example but also a secret union by which we are joined to him. Consequently, reviving us by his Spirit, he transfers his own power to us.

Therefore, just as the graft shares the same life or death with the tree into which it is ingrafted, so it is reasonable that we should be partakers of Christ's life no less than of his death. For if we are ingrafted according to the likeness of Christ’s death, which was not without a resurrection, then our death will not be without a resurrection.

However, the words allow for a twofold explanation: either that we are ingrafted in Christ into the likeness of his death, or that we are simply ingrafted in its likeness. The first reading would require the Greek dative ὁμοιώματι to be understood as indicating the manner. I do not deny that it has a fuller meaning, but as the other harmonizes more with simplicity of expression, I have preferred it, though it matters little, as both interpretations lead to the same meaning.

Chrysostom thought that Paul used the expression likeness of death for death itself, just as he says in another place, being made in the likeness of men. But it seems to me that there is something more significant in the expression. It not only serves to suggest a resurrection, but it also seems to indicate this: we do not die a natural death as Christ did, but there is a similarity between our death and his. For as he, by death, died in the flesh, which he had assumed from us, so we also die in ourselves, that we may live in him. It is not, then, the same death, but a similar one; for we are to notice the connection between the death of our present life and spiritual renewal.

Ingrafted, etc. There is great force in this word, and it clearly shows that the Apostle does not exhort, but rather teaches us what benefit we derive from Christ. For he requires nothing from us that is to be done by our own attention and diligence, but speaks of the grafting made by the hand of God.

However, there is no reason why you should seek to apply the metaphor or comparison in every particular. For between the grafting of trees and this spiritual grafting, a disparity will soon become apparent. In the former, the graft draws its nourishment from the root but retains its own nature in the fruit. But in the latter, not only do we derive the vigor and nourishment of life from Christ, but we also pass from our own nature to his.

The Apostle, however, meant to express nothing else but the efficacy of Christ's death, which manifests itself in putting our flesh to death, and also the efficacy of his resurrection, in renewing a spiritual nature within us.