Galatians 3:10-14 meaning

Here, Paul makes a very simple argument: If you think that it is through obeying the Old Testament law that you can gain a right standing with God, then you will never get there. The law says that everyone who does not [obey] all things written in the book of the law has failed, and is cut off from God. In fact, anyone who does not keep the law perfectly is under a curse. No one has perfectly obeyed the law, and no one can. So why would it make sense to try to gain a right standing with God by perfectly obeying the law (which is impossible)?

Paul quotes a passage from the Old Testament in Habakkuk 2:4: "The righteous man shall live by faith," or in other words, the only way to gain right standing (righteousness) with God is through faith. There is nothing new about this. It was true for Abraham, all the way back in Genesis. And it was true during the time of the Kings of Israel, in the book of Habakkuk. And it is true today.

Paul then points out that the law and faith are separate, because if you practice the law and think that it will create right standing with you before God, then you live by the law and not by faith.

But Christ's sacrifice for us on the cross—his death, burial, and resurrection—redeemed us from the curse of the Law. Jesus hung on a wooden cross, a tree, and incurred the curse written in Deuteronomy 21:23: Cursed is everyone who hangs on a tree. By dying on a cross, Jesus became a curse for us, and redeemed us from the curse of the Law. The Law demanded that all who were under it had to always obey it, and if they ever made one single mistake, they were cursed. On the cross, however, Christ took that curse on himself and sacrificed himself in our place.

Paul then ties Jesus back to Abraham. Jesus was not only Abraham's physical offspring, but also the fulfillment of God's promise to Abraham: that all nations would be blessed through him. In Christ Jesus the blessing of Abraham might come to the Gentiles (non-Jews), because through faith we all can gain right standing with God.