For it is written, that Abraham had two sons, the one by a bondmaid, the other by a free woman.
All Commentaries on Galatians 4:22 Go To Galatians 4
John Chrysostom
AD 407
He returns again to Abraham, not in the way of repetition, but, inasmuch as the Patriarch's fame was great among the Jews, to show that the types had their origin from thence, and that present events were pictured aforetime in him. Having previously shown that the Galatians were sons of Abraham, now, in that the Patriarch's sons were not of equal dignity, one being by a bondwoman, the other by a free-woman, he shows that they were not only his sons, but sons in the same sense as he that was freeborn and noble. Such is the power of Faith.