The Galatians who had responded to Paul’s gospel preaching of salvation by grace through faith were now falling away unto an anti-gospel of salvation by works through the influence of some agitators who were insisting that they receive circumcision and other prescriptions of the Mosaic code. Paul had no problem with those Jews saved by grace who chose to follow through with circumcision and the dietary laws as was their custom as Jews. But he had a major problem with imposing such matters on Gentiles and especially under the guise that such was necessary for salvation. Such law-keeping was the very opposite of salvation by grace, and he would fight it tooth and nail.
And Paul’s method of fighting this false understanding was through Scripture, which is always the best way of fighting heresy. He turns to Deuteronomy 27:26 to show just how demanding the law really is: “Cursed be everyone who does not abide by all things written in the Book of the Law and do them.” Thus, everyone who relies on works of the law for salvation is actually laboring under a curse. So it is then obvious that by such works no one shall be justified (made right) before God but only by faith—which is exactly how Abraham, the father of the Jews, was saved. Moreover, we look not to the law for justification but to Jesus who took the curse of the law on himself by hanging from a tree, citing again Deuteronomy 21:23. What this means is that the law-keeper became a curse for us by taking all of our “law-breakings” (i.e., sins) upon himself in our stead. In theology this is called our Lord’s “substitutionary atonement” whereby he reconciles us unto the Father through his own cleansing blood. He thereby releases us from the curse of the law, which is expressed by law-keeping, and frees us by rebirth through the Holy Spirit.
And so we are confronted by the gospel of grace and the anti-gospel of works; indeed, anything other than the gospel of grace which Paul and all the apostles preached is an anti-gospel. And this gospel is all predicated upon our Savior’s work on the cross to which our sins were nailed once and for all. So please be careful that you do not fall back under the curse from which you were released. You will never be good enough; you will never be able to do enough. Your conscience will never be clear before the law; it is a slave driver by nature, and a cruel one. Trust in Christ, cling to him; let his righteousness be your only plea. Then shall you be free to serve others in love without fear and with a clear conscience. Cursed be the curse.