Why does the promised blessing of Abraham come through faith in Christ rather than through the Mosaic law?

Atlas of Saints · Chapter summary

The promised inheritance was confirmed to Abraham and his Seed centuries before the law, which served only as a temporary custodian because of sin until Christ redeemed believers from the curse of the law and united all nations in Himself.

Chapter breakdown

Paul sharply rebukes the Galatians as senseless, demanding who has bewitched them into abandoning the truth after Jesus Christ was vividly portrayed before their very eyes as crucified among them. He challenges them to answer whether they received the Holy Spirit by performing deeds of the Mosaic law or through the responsive hearing of faith. Having begun their journey in the Spirit, he asks how they could foolishly imagine reaching perfection through the flesh, questioning whether their great sufferings have been in vain and adding the qualification, if it is yet in vain. God bestows the Holy Spirit and works wonders in their midst not through legal observances, but through faith. Citing sacred scripture, Paul recalls that Abraham placed his trust in God, and that belief was credited to him as righteousness; consequently, those who live by faith are the genuine children of Abraham. Foreseeing that the Gentiles would be justified by faith, scripture announced beforehand to the patriarch that all nations would find blessing in him, meaning that those who rely on faith share in the blessing of faithful Abraham.

In stark contrast, all who rely upon the works of the law remain under a curse, for sacred text pronounces cursed anyone who fails to persevere in everything written in the book of the law. That legal observance cannot justify anyone before God is evident, because scripture affirms that the just man shall live by faith, whereas the law does not operate from faith but demands that whoever performs its mandates must find life in them. Christ rescued believers from the curse of the law by becoming a curse on our behalf, fulfilling the passage that declares cursed anyone hanging upon a tree. Through this redemption, the blessing of Abraham reached the Gentiles in Christ Jesus, enabling all believers to receive the promised Holy Spirit through faith.

Using a common human illustration, Paul observes that once a person's covenant is formally ratified, no one sets it aside or appends conflicting terms. The divine promises were spoken directly to Abraham and to his singular offspring—not referring to many descendants, but designating one, who is Christ. The sacred covenant established by God four centuries and thirty years prior could not be invalidated by the subsequent introduction of the Mosaic code so as to make the promise void. If the spiritual inheritance depended on legal adherence, it would no longer stem from promise; yet God freely bestowed it upon Abraham through divine promise. The law was added because of transgressions until the arrival of the promised Seed, delivered through angels by the hand of a mediator. Challoner's gloss explains that the law was introduced because of transgressions to restrain people from sin by fear and threats; angels spoke in God’s name and person to Moses, mediator between God and the people. A mediator represents more than one party, but God is one.

The law did not contradict divine promises, for had a code been given that could bestow life, righteousness would indeed have come through legal observance. Instead, scripture confined all humanity under sin, so that the blessing promised through faith in Jesus Christ might be granted to those who believe. Challoner explains that scripture concluded all under sin by declaring every person trapped in sin from which deliverance is possible only through faith in the promised Seed. Prior to the revelation of faith, humanity was held under protective custody beneath the law, which served as our pedagogue leading toward Christ to attain justification by faith. Challoner clarifies that a pedagogue signifies a schoolmaster, conductor, or instructor. Now that the era of faith has arrived, believers are no longer under that custodian. All are made sons of God through faith in Christ Jesus, having put on Christ through holy baptism. Within this new life, Paul declares oneness in Christ: there is neither Jew nor Greek, slave nor free, male nor female, for all form one body in Christ Jesus, with the edition explaining that there is no distinction of Jew and the other listed categories. Belonging to Christ, believers are the true offspring of Abraham and legitimate heirs according to the promise.

The story inside

Context: The Galatians, having received the Holy Spirit through the hearing of faith, are being tempted by legalistic teachers to seek spiritual perfection through Mosaic ceremonial works.

Stakes: Succumbing to the law places believers under a divine curse, rendering their past sufferings in vain and threatening to forfeit the gratuitous inheritance promised to Abraham.

Action/Reasoning: Paul demonstrates that Abraham was justified by faith prior to the law, that scripture foresaw the justification of Gentiles, and that Christ redeemed believers from the curse of the law by hanging upon the tree; he argues from covenant law that the Mosaic code enacted 430 years later could not annul the original divine promise made to Abraham's singular Seed (Christ), explaining that the law was added merely as a temporary pedagogue to expose sin until the arrival of faith.

Consequence: Believers are no longer subject to the custodian; through baptism into Christ, they have put on Christ, described as one in Christ whether Jew or Greek, bond or free, male or female to become Abraham's true heirs.

Limit: The law was not contrary to God's promises, but simply lacked the power to impart life or righteousness, serving its defined purpose until faith was revealed.

Lessons worth keeping

1
The Primacy of the Abrahamic Covenant Over the Mosaic Law: God's covenant with Abraham was established upon faith and confirmed 430 years before the giving of the law; because human covenants cannot be arbitrarily altered once ratified, the subsequent introduction of the Mosaic code could not annul God's prior promise of gratuitous inheritance.
2
Christ's Redemptive Deliverance from the Curse of the Law: The law pronounces a curse upon everyone who fails to keep all its precepts, but Christ ransomed believers from this condemnation by bearing the curse on their behalf upon the cross, opening the Abrahamic blessing to all Gentile nations through the Holy Spirit.
3
The Pedagogical Function of the Law and Christian Sonship: The law operated as a temporary schoolmaster to restrain sin by fear and threats until the coming of Christ; once faith has arrived, baptized believers become children of God, united as one in Christ beyond all ethnic, social, or gender divisions.

Test your recall

How does the historical timeline of the covenant given to Abraham demonstrate that the inheritance does not depend on the Mosaic law?

Source edition and notes

Douay–Rheims, revised by Richard Challoner (1749–1752). Project Gutenberg no. 1581. Locators refer to lines in the admitted pg1581.txt edition. Source notes may include Challoner commentary.

Lines 131979–131989
3:6. As it is written: Abraham believed God: and it was reputed to him unto justice. 3:7. Know ye, therefore, that they who are of faith, the same are the children of Abraham. 3:8. And the scripture, foreseeing that God justifieth the Gentiles by faith, told unto Abraham before: In thee shall all nations be blessed. 3:9. Therefore, they that are of faith shall be blessed with faithful Abraham.
Lines 132001–132006
3:13. Christ hath redeemed us from the curse of the law, being made a curse for us (for it is written: Cursed is every one that hangeth on a tree). 3:14. That the blessing of Abraham might come on the Gentiles through Christ Jesus: that we may receive the promise of the Spirit by faith.
Lines 132015–132024
3:17. Now this I say: that the testament which was confirmed by God, the law which was made after four hundred and thirty years doth not disannul, to make the promise of no effect. 3:18. For if the inheritance be of the law, it is no more of promise. But God gave it to Abraham by promise. 3:19. Why then was the law? It was set because of transgressions, until the seed should come to whom he made the promise, being ordained by angels in the hand of a mediator.
Lines 132054–132060
3:26. For you are all the children of God, by faith in Christ Jesus. 3:27. For as many of you as have been baptized in Christ have put on Christ. 3:28. There is neither Jew nor Greek: there is neither bond nor free: there is neither male nor female. For you are all one in Christ Jesus.