1. The Historical Example (vs. 21-23)
    • 21 Tell me, you who desire to be under the law, do you not listen to the law? Paul confronts the Galatians for not knowing the very Law they want to be under. NKJV Study Bible, “Appropriately, Paul counters the Jewish false teachers’ zeal for the law with an argument based on the Law, the Pentateuch (Gen. 16:15; 21:2). He uses allegory to prove his point because it was a rhetorical technique the false teachers used. In other words, Paul was demonstrating that he could argue from the Law just as well as they could, but to prove that the Law of Moses pointed to the Messiah, Jesus Christ.”
    • 22 For it is written that Abraham had two sons, one by a slave woman and one by a free woman. Up to this point, Paul has argued that the Galatians have been united to Christ through faith, and therefore, are the true seed of Abraham (3:29). Paul now returns to Abraham, his primary argument to stress (once more) that the Law cannot save you from your sins. Abraham had two sons—The first contrast: slave vs. free. Ishmael, the older son, was born to Sarah’s slave, Hagar (Gen. 16) and Isaac, the younger son, was born to Abraham’s wife, Sarah (Gen. 21:1-6).
    • 23 But the son of the slave was born according to the flesh, while the son of the free woman was born through promise. The second contrast: ordinary birth with no promise vs. special birth with promise. Abraham and Sarah attempted to have a son outside the plan of God. Ishmael was born in the ordinary sense without the promises of God. Isaac, on the other hand, came into the world through the promises of God. By setting forth the biblical narrative of Abraham’s two sons, Paul then contrasts the son of the slave and son of the free woman. A clear distinction between religiosity constructed by man and God’s covenantal grace offered through Jesus Christ.
  1. The Allegorical Interpretation (vs. 24-27)
    •  24 Now this may be interpreted allegorically: these women are two covenants. One is from Mount Sinai, bearing children for slavery; she is Hagar. 25 Now Hagar is Mount Sinai in Arabia; she corresponds to the present Jerusalem, for she is in slavery with her children. The third contrast: Mount Sinai (old covenant) vs. Jerusalem (new covenant). To clinch his argument about being free from the Law because of Christ (2:20; 3:13), Paul draws out a deeper meaning of the births of Ishmael and Isaac. Interpreted allegorically—The method of allegorical teaching was very common in Jewish teachings. These women are two covenants—The first covenant is when God gave his Law to Moses on Mount Sinai (see Ex. 19-34). Hagar represents the Law and bondage.
    • 26 But the Jerusalem above is free, and she is our mother. God made the city of Jerusalem the place where he dwelt with his people. Ps. 78:67-68, “He rejected the tent of Joseph; he did not choose the tribe of Ephraim,68 but he chose the tribe of Judah, Mount Zion, which he loves.” However, Christ will bring the true Jerusalem from heaven to earth one day. Thus, the question that Paul poses to the Galatians is whether they will stick to the old legalistic Jerusalem on earth or return back to the liberty found in the heavenly Jerusalem?
      • Christ is the true temple.
        • John 2:18-22: So the Jews said to him, “What sign do you show us for doing these things?” 19 Jesus answered them, “Destroy this temple, and in three days I will raise it up.” 20 The Jews then said, “It has taken forty-six years to build this temple, and will you raise it up in three days?” 21 But he was speaking about the temple of his body. 22 When therefore he was raised from the dead, his disciples remembered that he had said this, and they believed the Scripture and the word that Jesus had spoken.
      • The true Jerusalem is in heaven.
        • 12:22, “But you have come to Mount Zion and to the city of the living God, the heavenly Jerusalem, and to innumerable angels in festal gathering”
        • 21:2, “And I saw the holy city, new Jerusalem, coming down out of heaven from God, prepared as a bride adorned for her husband.”
    • 27 For it is written, “Rejoice, O barren one who does not bear; break forth and cry aloud, you who are not in labor! For the children of the desolate one will be more than those of the one who has a husband.” Paul quotes from Isa. 54:1 to capture the prophetic words of Israel’s future deliverance from exile. The word of Isaiah is meant to bring hope and joy to the Jews. More Jews will live in freedom than in bondage.
  1. The Personal Application (vs. 28-31)
    • 28 Now you, brothers, like Isaac, are children of promise. 29 But just as at that time he who was born according to the flesh persecuted him who was born according to the Spirit, so also it is now. The fourth contrast: persecutor vs. persecuted. Paul paints a striking parallel between Abraham’s situation in Genesis with his two sons and the conflict he faced with the Galatians. Either the Galatians turn back to bondage or they choose to walk in grace. Persecuted him who was born—Refers to Isaac being tormented by his older brother, Ishmael (Gen. 21:9-10).
    • 30 But what does the Scripture say? “Cast out the slave woman and her son, for the son of the slave woman shall not inherit with the son of the free woman.” The fifth contrast: cast away vs. the heir. Eventually, Hagar and Ishmael were sent away because they had no rights to Abraham’s inheritance. Christ has set us free from the bondage of sin and death.
      • 6:6-11, “We know that our old selfwas crucified with him in order that the body of sin might be brought to nothing, so that we would no longer be enslaved to sin. For one who has died has been set free from sin. Now if we have died with Christ, we believe that we will also live with him. We know that Christ, being raised from the dead, will never die again; death no longer has dominion over him. 10 For the death he died he died to sin, once for all, but the life he lives he lives to God. 11 So you also must consider yourselves dead to sin and alive to God in Christ Jesus.”
    • 31 So, brothers, we are not children of the slave but of the free woman. Even as Isaac is the son of promise who will receive his faither’s inheritance, so are we (children of God) who put our faith in Jesus Christ. We do not receive the promises of God by observing the Law or by works.