The Pulpit Commentary - Genesis 17:1
And when Abram was ninety years old and nine —consequently an interval of thirteen years had elapsed since the birth of Ishmael; the long delay on the part of God being probably designed as chastisement for Abram's second nuptials (Calvin), and at least corresponding with Abram's undue haste (Lange)— the Lord appeared to Abram— lest he should regard Ishmael's birth as a complete fulfillment of the promise (Menochius), and be satisfied with Hagar's child as the expected seed (Calvin)— ... read more
John Calvin's Commentary on the Bible - Genesis 17:7
Verse 7 7.And thy seed after thee There is no doubt that the Lord distinguishes the race of Abraham from the rest of the world. We must now see what people he intends. Now they are deceived who think that his elect alone are here pointed out; and that all the faithful are indiscriminately comprehended, from whatever people, according to the flesh, they are descended. For, on the contrary, the Scripture declares that the race of Abraham, by lineal descent, had been peculiarly accepted by God.... read more