AJ Bandstra (The Law and The Elementa of The World An Exegetical Study In Aspects of Pauls Teaching) takes Paul’s distinguishes “heir” and “slave” in Galatians 4:1, the first referring to Jews and the second to Gentiles. Chapter 3 ends with Paul’s ringing declaration that those who are baptized into Christ as clothed in Christ and thus heirs according to promise. 4:1 turns the clock back to consider the situation prior to Christ, and there his point is “the Jew, who by Paul is considered to be the heir according to the flesh, ‘is no better off’ than the Gentile, the slave.” Verse 7 supports this interpretation: Addressing Gentiles in the second person, Paul says “you are no longer a slave but a son.”
This fits the logic of Galatians 4:1-3: In his minority, the heir is like a slave, under guardians and managers; and in the same way “we” (i.e., “we Jews”) were in bondage under the elements of the world. And, as Bandstra notes, it implies that Jews and Gentiles had something in common: “Just in this living according to the law and according to the flesh Paul finds the common denominator between Jewish religion and the pagan religions, of all religious practice before and outside of Jesus Christ” (63).
Paul, the historian of religions. Paul, the comparative religionist.