In Galatians 4, the Spirit draws another comparison between “two covenants.”
Tell me, you who desire to be under the law, do you not listen to the law? For it is written that Abraham had two sons, one by a slave woman and one by a free woman. But the son of the slave was born according to the flesh, while the son of the free woman was born through promise. Now this may be interpreted allegorically: these women are two covenants. One is from Mount Sinai, bearing children for slavery; she is Hagar. Now Hagar is Mount Sinai in Arabia; she corresponds to the present Jerusalem, for she is in slavery with her children. But the Jerusalem above is free, and she is our mother. 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.” Now you, brothers, like Isaac, are children of promise. 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. 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.” So, brothers, we are not children of the slave but of the free woman. (Galatians 4:21-31)
The following chart may help to visualize the contrasts:
THE MOUNT SINAI COVENANT 4:24
Like Hagar, Ishmael’s mother 4:22, 24, 25
Her son from ordinary birth 4:23, 29
Like earthly Jerusalem 4:25
In slavery 4:22, 24, 25, 31
Cast out—not to be heir 4:30
THE BETTER COVENANT
Like Sarah, Isaac’s mother 4:22, 23, 28
Her son from God’s promise, and Spirit 4:23, 28, 29
The Jerusalem above 4:26
Has freedom 4:22, 26, 31
Made the heir 4:30
Paul repeatedly tells his Christian readers that they belong to the covenant which is free like Sarah and her child. They do not belong to the covenant from Mount Sinai which is “bearing children for slavery” (Galatians 4:24). Indeed, such slaves have no inheritance with God’s people (Galatians 4:30).
Can that be right, that belonging to the New Covenant is a matter of inheritance or disinheritance, life or death? (For more on this question, see Endnote 2 https://wbslibrary.org/wp-admin/post.php?post=5566&action=edit.)