“For just as through the disobedience of the one man(Adam) the many were made sinners, so also through the obedience of the one man(Christ) the many will be made righteous.”
Imputation : In theology, ascribe (righteousness, guilt, etc.) to someone by virtue of a similar quality in another: for example, “Christ’s righteousness has been imputed to us.”
As Adam was the natural head of his posterity, so Christ is the spiritual Head of His people. Adam’s descendants are born from him according to the flesh, and possess the nature which existed in him as its beginning or fountain. Christ’s people are born of the Spirit, and possess the spirit which was in Christ without measure; so that, “If any man have not the Spirit of Christ, he is none of His” (Romans 8:9). This union is like that of the head and members of the human body: “and by one Spirit believers are all baptized into this one body” (1 Corinthians 12:13).
It is like the union of the vine and its branches; through all which the same vitalizing and fructifying sap circulates. This union secures the perfect consent, which has already been notice, between Christ and His people; and further illustrates the fitness of that arrangement by which they are regarded as one in the administration of God’s moral government.
As Adam was the federal head and representative of his descendants; so Christ stood, in the covenant of grace, as the federal head and representative of all whom the Father gave to Him. For their sakes He undertook the work of mediation; and for their sakes He did and suffered all that was necessary to the full execution of the work.
Justice, and every other attribute of the Divine nature, concurred in the arrangement, by which “He was to see of the travail of His soul and be satisfied; and by the knowledge of Him to justify many” (Isaiah 53:11). And now, justice, and every other attribute of the Divine nature, fully sanction the arrangement, by which His righteousness is imputed to all His elect people, on their believing in Him. : “Who shall lay anything to the charge of God’s elect? It is God Who justifies. Who is he that condemns? It is Christ Who died” (Romans 7:33-34).
The imputation of Adam’s sin to his posterity, is an act of justice; the imputation of Christ’s righteousness to believers, is an act of grace. The former is on the proper level of justice; but the latter rises above it. Justice has nothing to say against it, but, on the contrary, is fully satisfied and abundantly honored by it; yet the plan did not originate in the justice, but in the love, of God, which provided the needed sacrifice. When we feel, in every power of our minds, that we are justly condemned before God, and that His wrath is our righteous due; we can then receive Christ and salvation by Him, as the gift of God, the free gift, the unspeakable gift, of His grace.