In Context

15 And God saith unto Abraham, 'Sarai thy wife — thou dost not call her name Sarai, for Sarah is her name;

16 and I have blessed her, and have also given to thee a son from her; and I have blessed her, and she hath become nations — kings of peoples are from her.'

17 And Abraham falleth upon his face, and laugheth, and saith in his heart, 'To the son of an hundred years is one born? or doth Sarah — daughter of ninety years — bear?'

18 And Abraham saith unto God, 'O that Ishmael may live before Thee;'

19 and God saith, 'Sarah thy wife is certainly bearing a son to thee, and thou hast called his name Isaac, and I have established My covenant with him, for a covenant age-during, to his seed after him.

20 As to Ishmael, I have heard thee; lo, I have blessed him, and made him fruitful, and multiplied him, very exceedingly; twelve princes doth he beget, and I have made him become a great nation;

Genesis 17:18 in Other Translations