For it is written that Abraham had two sons, one by a slave and one by a free woman. But the son of the slave was born according to the flesh, the son of the free woman through promise.
Now this is an allegory: these women are two covenants. One is from Mount Sinai, bearing children for slavery; she is Hagar. 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 shout, you who are not in travail; for the children of the desolate one are many more than the children of her that is married."
So, brethren, we are not children of the slave but of the free woman.
-- Galatians 4: 22 - 24, 26 - 27, 31
