Commentaries and Other Bible Study Helps - Prayer Tents - Prayer Tents

4:21-31 The Gospel in the OT
4:21 law . . . law. Paul plays on the different senses of "law": it can mean the commandments given by God to Moses during the wilderness wanderings (which the Galatians misguidedly want to obey in their totality), but it can also mean the first five books of the Bible as a whole.
4:23 Flesh represents human desires, principles, and the sin that contaminates them: Ishmael was the son born when Abraham and Sarah took matters into their own hands by trying to perpetuate their family line through Hagar. The promise is the absolute opposite of flesh, since it is a word from God that will be fulfilled by God (see Rom. 4:18-21), just as Isaac was born by God's miraculous work.
4:25 Arabia. See note on 1:17. in slavery. The city of Jerusalem ought to be the capital city of the "Israel of God" (6:16), but instead it remains a stronghold of Israel according to the flesh, i.e., Jews who have not turned to Jesus. As a result, the city is just as it was when occupied in Isaiah's day--enslaved.
4:26-27 All those who believe in Christ belong to the heavenly Jerusalem and are the true Israel. As Isaiah prophesied (Isa. 54:1), the exile did not spell the end for the people of God. God will again work supernaturally to bring about the (new) birth of children where there are none, even among the Gentiles.
4:28 like Isaac. In a way analogous to Isaac's miraculous birth, the Galatians have become God's children by an act of God's gracious and miraculous power, not by human effort.
4:29 so also it is now. Just as Ishmael persecuted Isaac (not explicitly mentioned in the OT, but suggested by Gen. 21:9), so now the Jews who seek justification by human effort are persecuting Christians who trust God's promise of justification by faith. In Gen. 16:4, when Hagar conceived, "she looked with contempt on her mistress." This too is mirrored in the fact that now non-Christian and pseudo-Christian Jews are persecuting Christians like Paul (as seen in Gal. 6:17). History is repeating itself.
4:30 Cast out the slave woman and her son, and, by implication, all those represented by them in this allegory, i.e., those who seek justification through their own efforts. This implies that those who teach the false gospel of justification by works should not be allowed to remain and teach in a church that follows Christ.