15We ourselves are Jews by birth and not Gentile sinners; 16yet we know that a person is not justified by works of the law but through faith in Jesus Christ, so we also have believed in Christ Jesus, in order to be justified by faith in Christ and not by works of the law, because by works of the law no one will be justified.
The point Paul clearly makes in these two verses is that regardless of whether you are Jew or Gentile, there is only one way to be saved – faith in Jesus Christ. “… a person is not justified by works of the law but through faith in Jesus Christ.” The error that maintains that some can be saved through the law is still with us. It is a denial of the Gospel and falls under the condemnation of Galatians 1:8-9.
All who do not have Jesus Christ are lost and need to be saved. No one who has died without Jesus Christ gets a second chance. There are many who claim to be Christians who will conclude that people are granted entrance into eternal life based on their response to the light they had. They teach that if someone who never heard the Gospel is faithful to the religious beliefs that he was taught, then God will count that as good enough to merit eternal salvation.
The New Testament specifically contradicts this. Romans 1:18-32, Romans 10:5-17 in particular tell us that salvation comes only through conscious faith toward Jesus Christ. To teach otherwise is to condemn a vast host of humanity to a Christless eternity.
The great missionary movements of history and current missionary efforts in the world are not wasting their time. They are needed, because people are dying outside of Jesus Christ and they need to be told the Gospel so that they will trust Jesus to save them from their sins.
Pray for people to hear and believe the Gospel. And be a part of the answer to you prayer – give the biblical Gospel to whoever God grants you opportunity.