21 But now the righteousness of God apart from the law is revealed, being witnessed by the Law and the Prophets,
This verse begins a new section of Romans. From 3:20 to 5:21 Paul argued God’s provision of His righteousness by the principle of justification. No one can come to justification before God without God’s provision. In this section we have wonderful doctrines such as propitiation, grace, imputation, justification, and redemption.
Thus, after setting forth the case against man that he is sinful, Paul now turned to the solution to man’s sin. It is possible for anyone to have a right standing before God but they must do it God’s way.
21 But [sharp contrast to 1:18-3:20] now [next phase of argument]
Paul now contrasted those who try to be justified before God by “deeds of the law” with those justified by faith. This is a major shift of subject in Romans. This next phase of the argument is what God did about the sinfulness of man. There is a striking contrast in the way God manifests Himself differently from the law.
God’s provision of His righteousness by belief in the cross to save our souls is a sigh of relief—“but now.” It is a righteousness that stands apart from the law; the law has no connection to it. The image never gives birth to the substance but the substance to the image.
the righteousness of God [justification]
God’s righteousness is His vindicating activity whereby He confers on men who believe a new status in His economy. Paul here returned to the theme of Romans (1:17). Justification is God’s declaring those who accept the death of Christ for their sins as right in His eyes. This is God’s justifying righteousness; it is a righteousness that comes from Him.
The word “righteousness” does not have a definite article, placing emphasis on the quality of righteousness; it is a different kind of righteousness—God’s righteousness.
It is important to distinguish “righteousness” as a divine attribute and the standard of righteousness that God requires to enter heaven. We must come to God on His terms, not ours. God must remain consistent with His standard of absolute righteousness. The argument of the book of Romans is to vindicate this righteousness.
Justification is not simply the subtraction of sin from our lives but the addition of God’s righteousness in our standing with Him.
Justification is the act by God whereby He declares the person who trusts Christ’s death for pay for sin as righteous as God Himself is righteous.
Php 3:9, and be found in Him, not having my own righteousness, which is from the law, but that which is through faith in Christ, the righteousness which is from God by faith . . .