By righteousness
Paul means
right standing with God; or
salvation.
Likely, Paul has in mind that Gentiles who have faith have right standing with God. We can detect that this is Paul’s meaning because that is how the term righteousness
was used by some of Paul’s contemporaries. Also, Paul himself uses the term righteousness’ in Romans 3:22 and Romans 3:25–26 to refer to something like right standing with God.
Some contend that by righteousness
Paul means salvation. So he is saying that the Gentiles who have faith have salvation. These contend that when Paul writes in Romans 3:25–26 that God is both the just and the justifier for those who have faith in Christ, he means that God has saved all who have faith in Christ.
The problem with this view is that while Paul says that the Gentiles who have faith are righteous, he also warns them not to fall away lest God does not spare them (Romans 11:17–24). That Paul warns even those with faith from falling away suggests there is a distinction between righteousness and salvation.
So when Paul writes that the Gentiles with faith have attained righteousness, he means that faith in Christ results in right standing with God.
Interpretation 1:
Righteousness
means right standing with God.
Summary:
God created humans to be in a relationship with him, but sin disrupts that relationship. Through faith in Jesus Christ, the relationship between God and Gentiles is established, so Gentiles have right standing with God.
Humans offend God when they create idols and sin, rupturing our relationship with the Creator. Through faith in Jesus Christ, that relationship is established, and the healing process can begin. We repent from sin, turn from it, and begin to walk in God’s ways.
Advocates:
Brendan Byrne
Douglas Moo
Leon Morris
Frank Thielman
Minor differences:
Our authors generally agree that when Paul says the Gentiles have attained righteousness by faith, he has in mind that Gentiles who have faith have right standing with God.
Douglas Moo refers to this right standing with God as forensic righteousness. He contends there is a difference between moral and forensic righteousness, where forensic righteousness is understood as having a right standing with God.1
Leon Morris agrees with Moo but does not classify the righteousness as forensic. Rather, he simply notes that Paul has in mind the thought of a right standing with God.
2
Arguments
Interpretation 2:
Righteousness means salvation.
Summary:
Through his sovereign decree God has chosen to save Gentiles who believe in Jesus Christ. Thus, the righteousness that is by faith is salvation.
Advocates:
John MacArthur
Arguments
Possible weaknesses
30 What shall we say, then? That Gentiles who did not pursue righteousness have attained it, that is, a righteousness that is by faith;