Chapters 3 and 4 are in the form of a doctrinal dialogue. Paul challenges the Galatians to acknowledge that the gospel is superior to the law. In chapter 3, he argues that justification and the life-bringing promise of the Spirit (v 14) are received through faith in Christ, not by works of law. In chapter 4, he argues that the restraints of the law belong to childhood or slave relationship, whereas the resource of the indwelling "Spirit of His Son" (v 6) enables "adult son" privileges as heirs of God.
Chapter 3: Under the Curse or Heirs of the Promise? Works of Law or Faith in Christ?
3:1-5 Argument From Their Own Experience: Blessing Of The Spirit
In chapter 2, Paul concluded that God bestows justification through Christs death, discharging us from the law. Now, to recover the Galatian believers to their senses, Paul presents five challenges from their own spiritual experience. Did they no longer value the crucified Christ (v 1)? Had they received the Spirit by faith or by works (v 2)? Could the life begun in the Spirit, now be perfected by the flesh (v 3)? Was the reproach they suffered all for nothing (v 4)? Did the Spirits ministry and miracles operate by faith or by works of law (v 5)?
3:6-14 Testimony of Old Testament Scripture Points to Redemption by Christ
Their experience is confirmed by Abraham; indeed faith in Gods promise identifies them as sons of Abraham (v 7). The promise of blessing to all nations in Abraham is the gospel of redemption in embryo. In stark contrast, the law itself bears witness that those clinging to works of law (v 10) are under the divine curse upon failure to fulfil its obligations. The prophet Habakkuk also bears witness that the justified one lives by faith. The logical outcome of the argument is that we needed deliverance from the laws curse. Christ graciously intervened to bear the curse for us by His crucifixion death. This releases the floodgates of divine blessing to the Gentile world, "the promise of the Spirit," through faith in Christ (v 14).
3:15-25 Precedence Of The Promise; Purpose Of Law
But does not the law supercede the earlier promise to Abraham? It cannot, for the promise to Abraham stands irrevocable and unalterable, as an unconditional covenant confirmed by God alone. Furthermore, the promise was also to Christ as the coming Seed and Redeemer (note Gen 22:18; John 8:56, in context of the father offering his beloved son). Inheritance must come to us through Him as a gift of grace, not through the conditional law covenant made in the interval. What then was the purpose of the law? Rather than providing an alternative way of blessing, it proved all as transgressors, under sin, and incapable of entering His inheritance in their own right. The law had then a temporary custodial and disciplinary role ("schoolmaster" means an appointed child guardian) in preparation for the faith way in the coming Savior for justification and life. It is therefore now redundant for believers!
3:26-29 Perfection In Christ: Heirs Of The Promise
"All sons of God" (v 26), and "all one in Christ Jesus" (v 28), express the new relationship to God through faith in Christ. The parallel language with 1 Corinthians 12:13 and Colossians 3:11 suggests we are Christs as being part of His body, by new creation power of the Spirit. Thus we are also "Abrahams seed and heirs according to the promise" (v 29).
Ch.4: Two Covenants - Who is the Heir?
4:1-7 Jews (Children) And Gentiles (Slaves) Given Sonship In Christ: Heirs Of God
Using a familiar illustration, Paul now insists that the Fathers appointed time for full privileges of sonship has arrived. Two great historical realities unmistakably identify this. God has "sent forth His Son" (v 4) in incarnation, and to Calvary to redeem Jews under the bondage of law, and Gentiles under bondage of sin and ignorance. Then, upon the exaltation of Christ, "God sent forth the Spirit of His Son" (v 6) to indwell believers, providing both evidence and enabling of sonship. "Abba, Father" expresses our conscious trust and submission to God as sons.
4:8-20 Pauls Perplexity: Why Return To Bondage?
Having been delivered from the abject slavery of false religion into the fulness of relationship as sons of God, how could they return to what is actually weak and beggarly (v 10), elementary, and ineffectual, consisting of outward observances and rituals? Again, Paul expresses his deep longing for them, pleading with them to remember the blessedness they had experienced. They had received him and his message, despite an unappealing physical infirmity (possibly involving his eyesight). They had bonded so closely to him, they would have given their own eyes to help him! Was his faithfulness to them now going to be treated as enmity? Others were courting them zealously, not for their benefit, but only to exclude them from Paul. As their spiritual father, his interest remains true as at the beginning, to see Christ formed in them. But he feels perplexed, as many parents do with wayward children.
4:21-31 Allegory Of The Two Covenants: Abrahams Two Sons
His final argument to those inclining towards the law is an allegory drawn from Abraham and his two sons. Two significant details provide an illustration of the two covenants. Hagar was a bondmaid, and Ishmaels birth was by human scheming and strength; Sarah was a free woman, and Isaacs birth was by a divine promise requiring divine power for its fulfilment. Hagar corresponds to the law covenant given at Mt. Sinai, connecting logically to earthly Jerusalem and "her children" under law. These are all natural descendants of Abraham, but in bondage. In contrast, the barren Sarah corresponds to the heavenly Jerusalem, whose place and progeny depend entirely upon divine promise for fulfilment (Heb 11:10,16; 12:22). Like Isaac, we are "the children of promise," "born after the Spirit" (v 28). A further insightful parallel is drawn: like Isaac, presently persecuted by those born after the flesh, the Judaizers. But the reversal quickly follows: both the bondwoman and her son are removed, and Isaac alone is heir. The conclusion of the allegory is self-evident: we who are of the free are the true heirs.