Abraham... laughed. — The Jewish interpreters regard Abraham’s laugh as one of joy, and Sarah’s (Genesis 18:12) as one of unbelief. We may, however, well doubt whether there really was this difference between them; but our Lord confirms the View that joy was uppermost in Abraham’s heart (John 8:56). Still with belief there was surprise, and the feeling that what was promised was so strange as to be well-nigh incredible. One who was ready to sacrifice his only son at God’s word (Hebrews 11:19) would not be staggered by this strangeness, and yet the thought of Sarah’s bearing a child at the age of ninety might easily present itself to his mind in a ludicrous aspect. As for Sarah, there is no proof that at the time when she laughed she knew or even suspected that the three travellers were more than men. She overheard their conversation, and laughed, imagining perhaps that they did not know how old she was. Really, the idea brought out by this double laughter is that Isaac’s birth was contrary to nature.
Related Commentaries of Genesis 17:17
Genesis 17:17
17 Then Abraham fell upon his face, and laughed, and said in his heart, Shall a child be born unto him that is an hundred years old? and shall Sarah, that is ninety years old, bear?