Galatians 4:21 Tell me, you who desire to be under the law, do you not hear the law? 22 For it is written that Abraham had two sons: the one by a bondwoman, the other by a freewoman. 23 But he who was of the bondwoman was born according to the flesh, and he of the freewoman through promise, 24 which things are symbolic. For these are the two covenants: the one from Mount Sinai which gives birth to bondage, which is Hagar— 25 for this Hagar is Mount Sinai in Arabia and corresponds to Jerusalem which now is, and is in bondage with her children— 26 but the Jerusalem above is free, which is the mother of us all. 27 For it is written:  “Rejoice, O barren, you who do not bear!  Break forth and shout, you who are not in labor!  For the desolate has many more children than she who has a husband.” 28 Now we, brethren, as Isaac was, are children of promise. 29 But, as he who was born according to the flesh then persecuted him who was born according to the Spirit, even so it is now. 30 Nevertheless, what does the Scripture say? “Cast out the bondwoman and her son, for the son of the bondwoman shall not be heir with the son of the freewoman.” 31 So then, brethren, we are not children of the bondwoman but of the free.

In these passages, we find that another gospel had been introduced at Galatia—another gospel involves applying the law as part of God’s plan for what completes one’s salvation experience or enhances it. To dismantle a false gospel, Paul explained the two main covenants in Scripture and how one is meant to be cast away.  He demonstrates how Gentile believers embrace the law after coming to Jesus, opposing the real truth that Gentiles without the law are part of the heavenly Jerusalem.

The poem from Isaiah in the passages foretells how Gentiles without the law have always been a part of God’s plan of salvation, too.  They weren’t an afterthought.  God planned for righteousness apart from the Law that involved Christ and His New Covenant.

Romans 3:21 But now the righteousness of God apart from the law is revealed, being witnessed by the Law and the Prophets,

Paul called the Galatians back to the New Covenant Gospel to dispel the deception.

Galatians 3:1 O foolish Galatians! Who has bewitched you that you should not obey the truth, before whose eyes Jesus Christ was clearly portrayed among you as crucified? 2 This only I want to learn from you: Did you receive the Spirit by the works of the law, or by the hearing of faith? 3 Are you so foolish? Having begun in the Spirit, are you now being made perfect by the flesh?

Anytime the gospel's simplicity and purity are challenged in a believer's perspective, it is bewitching.  In other words, there are demonic forces at work seeking to dilute the purity and simplicity of the gospel.  The most effective way they have found to do this is by using a mixture.  By mixing law with grace, they sully the gospel and make the promises a maybe instead of yes and amen in Christ.

The enemy is after your understanding of the gospel, Christ, the Father, and the Holy Spirit, and what has been done for you to enjoy their love, acceptance, and help.  Satan wants to skew your perspective about God.

Bewitched in Greek means to be fascinated with false representations.  It is the same practice the enemy used against Eve in the garden when he called into question whether or not God really said what she had been told He said.

Law and grace are like water and oil.  They do not mix.  Law has a place when dealing with arrogant sinners who oppose the truth and argue for their own right standing based on their own merit or reject the notion that they need the help of Jesus in any way.  But it has no place with saints who have come to Christ in full assurance of faith resting on His completed work on their behalf.  Have you cast out the bondwoman?  Or do you think she can help you become more acceptable to God than what Jesus has already done on your behalf?  It is no gospel that encourages you to put your trust in what you can do to gain acceptance with God as your Father at any time during your journey.  The real gospel calls you to faith in Christ alone.  Cast out the bondwoman and her son!