21 Tell me, those of you who want to be under the law, don’t you hear the law? 22 For it is written that Abraham had two sons, one by a slave and the other by a free woman. 23 But the one by the slave was born according to the impulse of the flesh, while the one by the free woman was born as the result of a promise. 24 These things are illustrations, for the women represent the two covenants. One is from Mount Sinai and bears children into slavery—this is Hagar. 25 Now Hagar is Mount Sinai in Arabia and corresponds to the present Jerusalem, for she is in slavery with her children. 26 But the Jerusalem above is free, and she is our mother. 27 For it is written:
Rejoice, childless woman,
who does not give birth.
Burst into song and shout,
you who are not in labor,
for the children of the desolate are many,
more numerous than those
of the woman who has a husband.
28 Now you, brothers, like Isaac, are children of promise. 29 But just as then the child born according to the flesh persecuted the one born according to the Spirit, so also now. 30 But what does the Scripture say?
Drive out the slave and her son, for the son of the slave will never be a coheir with the son of the free woman.
31 Therefore, brothers, we are not children of the slave but of the free woman.