Genesis 17:16-19

16I will bless her and will surely give you a son by her. I will bless her so that she will be the mother of nations; kings of peoples will come from her.’

17Abraham fell face down; he laughed and said to himself, ‘Will a son be born to a man a hundred years old? Will Sarah bear a child at the age of ninety?’ 18And Abraham said to God, ‘If only Ishmael might live under your blessing!’

19Then God said, ‘Yes, but your wife Sarah will bear you a son, and you will call him Isaac.
Isaac means he laughs.
I will establish my covenant with him as an everlasting covenant for his descendants after him.
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