Genesis 17:20
And as for Ishmael, I have heard thee: Behold, I have blessed him, and will make him fruitful, and will multiply him exceedingly; twelve princes shall he beget, and I will make him a great nation. And as for Ishmael, I have heard thee: Behold, I have blessed him, and will make him fruitful, and will multiply him exceedingly; twelve princes shall he beget, and I will make him a great nation.
When Abraham was nearly one hundred years old he offered the affectionate prayer that Ishmael might live before God, and this promise is God's answer to that prayer. He prayed thus because he did not yet understand that the promised heir must be Sarah's child, but clung to the belief that God's gracious purposes would be accomplished through Ishmael. God stated unmistakably in reply that Sarah herself would bear Isaac and that the covenant would be established with Isaac, not with Ishmael. Yet mindful of the father's plea, He blessed Ishmael and promised to make him fruitful and multiply him exceedingly into a large people, a great nation, apart from the covenant. That blessing meant God would preserve Ishmael even though he would be sent away from Abraham's household.