This should be pondered again and again!

Galatians 2:11 ¶ But when Peter came to Antioch, I had to oppose him to his face, for what he did was very wrong.
12 When he first arrived, he ate with the Gentile Christians, who were not circumcised. But afterward, when some friends of James came, Peter wouldn’t eat with the Gentiles anymore. He was afraid of criticism from these people who insisted on the necessity of circumcision.
13 As a result, other Jewish Christians followed Peter’s hypocrisy, and even Barnabas was led astray by their hypocrisy.
14 When I saw that they were not following the truth of the gospel message, I said to Peter in front of all the others, “Since you, a Jew by birth, have discarded the Jewish laws and are living like a Gentile, why are you now trying to make these Gentiles follow the Jewish traditions?
15 “You and I are Jews by birth, not ‘sinners’ like the Gentiles.
16 Yet we know that a person is made right with God by faith in Jesus Christ, not by obeying the law. And we have believed in Christ Jesus, so that we might be made right with God because of our faith in Christ, not because we have obeyed the law. For no one will ever be made right with God by obeying the law.”
17 But suppose we seek to be made right with God through faith in Christ and then we are found guilty because we have abandoned the law. Would that mean Christ has led us into sin? Absolutely not!
18 Rather, I am a sinner if I rebuild the old system of law I already tore down.
19 For when I tried to keep the law, it condemned me. So I died to the law––I stopped trying to meet all its requirements––so that I might live for God.
20 My old self has been crucified with Christ. It is no longer I who live, but Christ lives in me. So I live in this earthly body by trusting in the Son of God, who loved me and gave himself for me.
21 I do not treat the grace of God as meaningless. For if keeping the law could make us right with God, then there was no need for Christ to die.

Galatians 3:1 ¶ Oh, foolish Galatians! Who has cast an evil spell on you? For the meaning of Jesus Christ’s death was made as clear to you as if you had seen a picture of his death on the cross.
2 Let me ask you this one question: Did you receive the Holy Spirit by obeying the law of Moses? Of course not! You received the Spirit because you believed the message you heard about Christ.
3 How foolish can you be? After starting your Christian lives in the Spirit, why are you now trying to become perfect by your own human effort?
4 Have you experienced so much for nothing? Surely it was not in vain, was it?
5 I ask you again, does God give you the Holy Spirit and work miracles among you because you obey the law? Of course not! It is because you believe the message you heard about Christ.
6 ¶ In the same way, “Abraham believed God, and God counted him as righteous because of his faith.”
7 The real children of Abraham, then, are those who put their faith in God.
8 What’s more, the Scriptures looked forward to this time when God would declare the Gentiles to be righteous because of their faith. God proclaimed this good news to Abraham long ago when he said, “All nations will be blessed through you.”
9 So all who put their faith in Christ share the same blessing Abraham received because of his faith.
10 But those who depend on the law to make them right with God are under his curse, for the Scriptures say, “Cursed is everyone who does not observe and obey all the commands that are written in God’s Book of the Law.”
11 So it is clear that no one can be made right with God by trying to keep the law. For the Scriptures say, “It is through faith that a righteous person has life.”
12 This way of faith is very different from the way of law, which says, “It is through obeying the law that a person has life.”
13 But Christ has rescued us from the curse pronounced by the law. When he was hung on the cross, he took upon himself the curse for our wrongdoing. For it is written in the Scriptures, “Cursed is everyone who is hung on a tree.”

The Galatians were already believers in Christ that much is clear so the argument is not that they were trying to be saved by the law. The argument is that after having received Christ by faith they were trying to add to their standing before God by keeping the law. Jewish teachers had come to them teaching something else is needed and they bit the hook. Beware teachings that try to add to what Christ has already completed in Himself.