“But before faith came, we were kept under guard by the law, kept for the faith which would afterward be revealed”
Verse 23 bears a strong semblance to verse 22. Verse 22 showed us that there are no supporting arguments to keep the law for salvation.
But before faith came,
The “faith” here is faith in Christ (3:22). The Greek says “the faith” indicating a special faith, faith in the promise of Jesus Christ (3:22). Old Testament saints did not have the opportunity to believe in the person of Jesus Christ. They believed in the coming Messiah.
“For the law was given through Moses, but grace and truth came through Jesus Christ” (John 1:17).
Paul now turns to the first person “we” referring to saved Jews. The law kept Jews in the prison of legalism during God’s dealings with Israel. The idea is that when Christ came, the object of faith changed from the idea of a coming Messiah to the person of Jesus. We came to understand who the Messiah was in His person and work.
Paul uses the second person plural “you” in the preceding context until this verse. Now he switches to the first person plural through verse 25. At verse 26, he reverts to the second person “you.” The whole argument of this section revolves around the first person plural “we.” Paul very carefully switched these pronouns for a purpose. The “we” are Jewish Christians in Galatia and “you” are Christian Gentile Galatians.
were kept under guard by the law,
The word “kept” is a military term for keeping guard as with a garrison. The law guards against every way of escape from the conclusion we are sinners. The phrase in verse 22 “confined all under sin” and this phrase “kept under guard by the law” is the same thing. The law will not allow us to justify our sin. Therefore, we cannot justify ourselves by works. All the law does to us is curse us. It proves we are sinners.
kept for the faith which would afterward be revealed
The second word for “kept” in this verse means to shut together, shut in on all sides. The law kept people in a state of exclusively depending on faith in the Messiah for salvation. This does not mean that God justified people by law before Christ, because God justified Old Testament believers by faith just as He justified Abraham by faith (Genesis 15:6).
The Greek word indicates the law permanently shuts us up to sin until the faith “afterward” revealed. The word “revealed” means uncovered. The faith of this dispensation was unknown under the law; it was covered until Christ came. The law covered New Testament faith for 1500 years. God locked the Jews under the law until Christ came to fulfil all the requirements of the law (Romans 8:2-4). God frees both Jews and Gentiles through personal faith in Christ. The Jews anticipated the coming of the Messiah and Gentiles know the Messiah by name.
The law is a prison to those who try to keep it.
The law can diagnose our sin but it cannot prescribe a remedy. If this is so, why would you revert to legalism to be saved or sanctified? The law precludes any attempt to secure justification before God other than by faith in the finished work of Christ. God does not want us to lose consciousness of our sin and it’s ability to punish us. If we keep the law to be saved, it will forever imprison us. However, if we trust the work of Christ, it will forever free us.
“Yet indeed I also count all things loss for the excellence of the knowledge of Christ Jesus my Lord, for whom I have suffered the loss of all things, and count them as rubbish, that I may gain Christ 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; that I may know Him and the power of His resurrection, and the fellowship of His sufferings, being conformed to His death, if, by any means, I may attain to the resurrection from the dead” (Philippians 3:8-11).