But it is not that the word of God has taken no effect. For they are not all Israel who are of Israel, 7 nor are they all children because they are the seed of Abraham; but, "IN ISAAC YOUR SEED SHALL BE CALLED." 8 That is, those who are the children of the flesh, these are not the children of God; but the children of the promise are counted as the seed. Romans 9:6-8

Even after God cut the covenant with Abraham, alas, Abraham still had no child. Eleven years later, at age 86, Abraham’s wife, Sarah, suggested that Abraham conceive a child with her maid, Hagar. Abraham followed his wife’s bad advice and Abraham had a son, Ishmael. From that point forward, there was strife between Sarah and Hagar. And we might add that from that time until this day, the children of Isaac (Jews), and the children of Ishmael (Arabs), has been anything but peaceful!

The Bible teaches that when we try to take the fulfillment of God’s promises into our own hands—especially in the strength of our flesh—the results are not only disastrous, but altogether unacceptable to God. Ishmael was not the son God promised to Abraham. Isaac (though not yet born at that time) was the son of Promise (Romans 9:6-8).

Though Abraham had to wait a long time for the fulfillment of God’s promise, God gave Abraham and Sarah a son 13 years later when Abraham was 100 years old and Sarah was 90. That son’s name was Isaac and God’s promised Seed (Jesus) came through Isaac, not Ishmael.