The book of Galatians makes it clear that we are no longer under bondage to the Old Testament law. We can now walk in the spirit, and do not need a law. Christ freed us from the law.
Galatians 2:21
I do not reject the grace of God. Moreover, if justness is through the law, then Christ died for no reason.
Galatians 5:1-4
1 Christ freed us with freedom. Therefore, stand fast and do not be entangled again with a yoke of bondage.
2 Behold, I, Paul, say to you that if you would become circumcised, then Christ will profit you nothing.
3 I testify again to every person who becomes circumcised that he is obliged to do the whole law.
4 You who seek to be justified by law have been made inactive from Christ. You have drifted away from the grace.
A work that was considered very important by some people at that time was circumcision. There can be many different works that people may consider important or necessary for salvation. Paul was saying to them that if they thought they needed to do some work to gain salvation, then Christ would profit them nothing! If you think you need to do works to be righteous before God, then you are not appreciating the completed work of Jesus Christ, his work will profit you nothing, and you’ve drifted away from appreciating God’s grace.
Romans 3:19-24
19 Now we know that whatever the law says, it speaks to those who are under the law, so that every mouth may be stopped and that all the world may become guilty before God.
20 Wherefore, no flesh will be justified before Him by the works of the law, for through the law is the knowledge [acknowledgment] of sin.
21 Now, however, the justice of God without the law has been manifested, being witnessed to by the law and the prophets.
22 Yes, the justice of God is by the believing of Jesus Christ to all those who believe, for there is no difference.
23 In fact, all have sinned and come short of the glory of God,
24 being justified freely by His grace through the redemption that is in Christ Jesus.
No one can become righteous before God by the works of the law. Even if we do some good things, we’ve all still sinned and come short of the glory of God. Thankfully, we can now be justified before God freely by His grace, just by believing on His son Jesus Christ.
Ephesians 2:8-10
8 By grace, you have certainly been saved [delivered] through believing, and this [salvation] is not from yourselves. It is the offering of God.
9 It is not of our works so that no one may boast,
10 for we are His workmanship, created in Christ Jesus on the basis of good works that God previously prepared, so that we may walk in them.
Simply by believing what God says has been accomplished by the completed work of His son Jesus Christ, we are saved by grace, not by our works.