In Galatians 3–4, Paul is arguing on three convergent lines. First, the promise was made unconditionally to Abraham. God’s covenant with him (Gen 15) preceded any precept of circumcision (Gen17). This covenant was pure grace on the part of God and was not prefaced on any ‘works.’ In a similar manner, God was now calling all peoples, Jews and Gentiles; a call based on God’s grace and not prefaced on ‘works.’
Second, the promise of God was made to Abraham and to his seed, in the singular and not in the plural (Gal 3,16). This emphasis indicates that Paul had before him a text that bore the words “and to your offspring” in the singular. The promise refers to the words of God to Abraham in Genesis 12,3 namely, “by you all the families of the earth shall bless themselves.” A repetition of this promise with the exact addition “and to your offspring” in the singular occurs in Genesis 13,15 and 17,8. In both cases the reference is to possession of the land. Here, Paul must have read land (ge) as the ‘inhabited earth.’ Both Greek ge and Hebrew eres are ambivalent. They can refer to the promised land of Canaan or to the whole inhabited earth. Because there is a Jewish tradition which views that the inheritance of God’s people is the whole earth (Matt 5,5; Cf. 1 Enoch 5,6-7; 4 Ezr 6,55-59). Romans 4,13 clearly points out what was promised to Abraham was that he would inherit the world. If the ‘seed’ of Abraham is singular and Abraham is promised the inheritance of the world, then Christ was promised inheritance of the world. Paul did not explicitly draw this conclusion in Galatians, but in Philippians 2,6-11, he says that everything on earth and in heaven is subjected to Christ and all must confess that Jesus Christ is the Lord to the glory of the Father.
The question then is how will God fulfil this promise to Abraham and to Christ that they will possess the world? That brings us to the third point.
Third, Galatians 3,14 relates the blessing of Abraham closely to “the promise of the Spirit” when it says “that in Christ Jesus the blessing of Abraham might come upon the Gentiles, that we might receive the promised Spirit through him.” The genitive “the promise of the Spirit” indicates identity and thus the content of the promise is the Spirit. But where is the Spirit promised to Abraham? Genesis 15,6 says that Abraham believed God and this was reckoned to him as righteousness. What he believed was God’s promise that his seed would be like the stars of heaven, even though at the moment he was childless and his wife was barren. But for Paul the promise of numerous descendants is the promise of the Spirit. Romans 4,18-21 describes the begetting of Isaac as “according to the Spirit.” Like Isaac, only those begotten ‘according to the Spirit’ are children of the promise. In other words, both for Abraham and for his seed/Christ, the true children who will inherit the world are those begotten not by the flesh but by the Spirit. It is the Spirit that made the Galatians to be “in Christ,” and simply by being Christ’s, you are the progeny of Abraham, the heir of the promise (Gal 3,29). Since the scripture foresaw that God would give saving justice to the Gentiles through faith, it announced the future Gospel to Abraham saying, “all nations will be blessed in you” (Gal 3,8). In other words, Genesis 15,6 and Habakkuk 2,4 (“the upright will live through faith,” Gal 3,11) make it clear that all along God envisaged only one demarcating line – not the ethnic line of Jew and Gentile, but that of faith. Faith is given by the Spirit which gives participation in the blessing of Abraham independently of circumcision and the law, as was the case with Abraham. Christ, the true seed of Abraham, communicates Abraham’s blessing to the Gentiles by bringing light to the nations.
 Cf. M. Silva, “Abraham, Faith, and Works: Paul’s Use of Scripture in Galatians 3.16-14,” WTJ, Vol. 63, no. 2, The Westminster Theological Seminary, Philadelphia, (2001), 251-267, 258-261.
 Cf. J. Phillips, Exploring Galatians: An Expository Commentary, Kregel Publications, Michigan, (2004), 90-92.
 Cf. R. Y. K. Fung, The Epistle to the Galatians: The New International Commentary on the New Testament, William B. Eerdmans Publishing Company, Michigan, (1989), 155.
 J. C. Okoye, Israel and the Nations: A Mission Theology of the Old Testament, Orbis Books, Maryknoll, New York, (2006), 52.
 Cf. J. Phillips, Exploring Galatians: An Expository Commentary, Kregel Publications, Michigan, (2004), 98-100.
 Cf. S. K. Williams, “Promise in Galatians: A Rereading of Paul’s Reading of Scripture,” JBL, Vol. 107, The Society of Biblical Literature, Atlanta, (1988), 709-720, 712.
 Cf. R. Y. K. Fung, The Epistle to the Galatians: The New International Commentary on the New Testament, William B. Eerdmans Publishing Company, Michigan, (1989), 151.
 J. C. Okoye, Israel and the Nations: A Mission Theology of the Old Testament, Orbis Books, Maryknoll, New York, (2006), 53.
 Cf. B. M. Newmann, ““Seed” in Galatians 3.16, 19,” The Bible Translator, Vol. 35, no. 3, The United Bible Societies, New York, (1984), 334-337, 335-336.
 Cf. R. Y. K. Fung, The Epistle to the Galatians: The New International Commentary on the New Testament, William B. Eerdmans Publishing Company, Michigan, (1989), 151-153.
 Cf. J. Kattackal, “The Call of Abraham and Faith-formation in the Book of Genesis,” BB, Vol. XVI, no. 2, Bible Bhashyam Trust, Kottayam, (1990), 69-78, 71-75.
 Cf. W. J. Dumbrell, “Abraham and the Abrahamic Covenant in Galatians 3:1-14.” in M. Thompson and P. Bolt (eds.), The Gospel to the Nations: Perspectives on Paul’s Mission, Intervarsity Press, Leicester, (2000), 19-31, 21.
 Cf. N. T. Wright, “Curse and Covenant: Galatians 3:10-14,” The Climax of the Covenant: Christ and the Law in Pauline Theology, T&T Clark Publishers, Edinburgh, (1991), 137-156, 154.