“Sinners who aren’t righteous are counted as righteous and considered as righteous, even though they are not righteous in themselves. They are counted to be something that is not theirs inherently.”

“Justification is both declarative and a constitutive act of God’s free grace. It is constitutive in order that it may be truly declarative. God must constitute the new relationship as well as declare it to be. The constitutive act consists in the imputation to us of the obedience and righteousness of Christ. The obedience of Christ must therefore be regarded as the ground of justification; it is the righteousness which God not only takes into account but reckons to our account when He justifies the ungodly.”

Now, in what sense did the Father “make” the Son “sin” on our behalf? In only one sense: the Father counted Jesus to have committed all the sins of all those who would ever repent and believe in him.

Though innumerable sinners will escape divine punishment, no sin will ever go unpunished, for every sin of the elect has been reckoned to Christ and punished in him on the cross.

Because they have been counted, or imputed, to Christ, the believer’s sins are not imputed to (or counted against) him. They are forgiven and covered. Therefore, the justified believer faces no condemnation (Rom. 8:1, 33–34) but enjoys peace with God (Rom. 5:1) and the sure hope of eternal life (Rom. 8:30; Titus 3:7).

But the forgiveness of sins does not exhaust God’s work in justification. In fact, if the only benefit believers received in justification were the forgiveness of our sins, we could not be saved. The old Sunday school definition of justification—“just as if I’d never sinned”—is inadequate, because salvation is not merely a matter of sinlessness or innocence but is also a matter of righteousness (Matt. 5:20, 48). The law of God, which man broke, thereby incurring the death penalty (Rom. 6:23), carries both positive demands and penal sanctions. That is to say, God’s law requires both (1) that his creatures perform certain duties suitable to his righteousness and (2) that they undergo a certain punishment if they fail to perform those duties. Man has failed to do both. We do not live lives of perfect righteousness, walking in obedience to God in all things, loving him with all our heart, soul, mind, and strength, and loving our neighbors as ourselves. Neither could we pay the penalty that our disobedience demands without perishing eternally in hell. Therefore, if we are to be saved, our substitute must not only pay our penalty by absorbing the wrath of God against our sin but must also obey all the positive demands of the law that were required of us. This twofold nature of Christ’s substitutionary work is sometimes referred to as his passive obedience and active obedience.

The law of God has both penal sanctions and positive demands. It demands not only the full discharge of its precepts but also the infliction of penalty for all infractions and shortcomings. It is this twofold demand of the law of God which is taken into account when we speak of the active and passive obedience of Christ. Christ as the vicar of his people came under the curse and condemnation due to sin and he also fulfilled the law of God in all its positive requirements. In other words, he took care of the guilt of sin and perfectly fulfilled the demands of righteousness. He perfectly met both the penal and the preceptive requirements of God’s law. The passive obedience refers to the former and the active obedience to the latter

With respect to justification, then, God not only satisfies the penal demands of the law by imputing our sin to Christ and punishing him in our place but also satisfies the positive demands of the law by imputing Christ’s righteousness to us.

In summary, in Christ we have a substitute who has both paid our penalty and achieved our righteousness. Christ provided forgiveness by atoning for our sins on the cross. Just as our sins were reckoned to his account when he died on the cross, in the same manner his righteousness is counted as ours. His perfect righteousness is thus the ground on which we stand before God. Sinners are not justified because of some good thing in them; God can declare us righteous—he can justify the ungodly and yet remain just—because he graciously imputes to us the perfect righteousness of his own dear Son. Thus, the sole ground of justification is the righteousness of Christ counted to be ours as a gift by grace alone