Genesis 17:18

And Abraham said unto God,.... Being told he should have a son by Sarah, that should be his heir, he is concerned for Ishmael what would become of him; and who, being grown up, had doubtless a large share in his affections, and it is highly probable he began to think he was the promised seed, since he had lived to such an age, and had no other son, and Sarah was past bearing children: but now perceiving it would be otherwise, he puts up a petition for Ishmael, whom he did not neglect upon the promise of another, and to show his love to him, and regard for his welfare:

O that Ishmael might live before thee; he prays that his life might be preserved, and that it might be spent in the fear, worship, and service of God; so the Targum of Jonathan,

"O that Ishmael might live and worship before thee,''

and to the same sense Jarchi also; that he might enjoy the favour of God, his gracious presence and communion with him; that he might live a holy spiritual life here, acceptable and well pleasing to God, and possess eternal life hereafter: for we must take this prayer in as large a sense as we can suppose the heart of a father to be drawn forth in it for the good of his child; though it may greatly respect his sharing with the promised son in his blessings, and particularly regards the propagation of his offspring, or his living in his posterity at least; this was what the Lord took notice of, and answered him in.