5:21 An important summary of the gospel message. The verse explains how God imputed our sin to Christ. God as judge assigned the responsibility of our sin to Christ, making it possible for Him to be punished justly for that sin (Is. 53:6; 1 Pet. 2:24). The verse shows that Christ was our substitute, accepting the penalty of sin in our place. See “The Sinlessness of Jesus” at Heb. 4:15.
we might become the righteousness of God. Not only did God impute our sin to Christ, He also imputed Christ’s perfect righteousness to us (that is, He counted it as belonging to us). This imputation is the basis for the progressive realization of God’s righteousness in our moral character. Our thoughts and deeds are sanctified in increasing measure until we receive perfect righteousness in heaven.