Discovery BoxGenesis 17:17 
Context17:17 Then Abraham bowed down with his face to the ground and laughed 1 as he said to himself, 2 “Can 3 a son be born to a man who is a hundred years old? 4 Can Sarah 5 bear a child at the age of ninety?” 6
Genesis 17:24
Context17:24 Now Abraham was 99 years old 7 when he was circumcised; 8
1 sn Laughed. The Hebrew verb used here provides the basis for the naming of Isaac: “And he laughed” is וַיִּצְחָק (vayyitskhaq); the name “Isaac” is יִצְחָק (yitskhaq), “he laughs.” Abraham’s (and Sarah’s, see 18:12) laughter signals disbelief, but when the boy is born, the laughter signals surprise and joy.
2 tn Heb “And he fell on his face and laughed and said in his heart.”
3 tn The imperfect verbal form here carries a potential nuance, as it expresses the disbelief of Abraham.
4 tn Heb “to the son of a hundred years.”
5 sn It is important to note that even though Abraham staggers at the announcement of the birth of a son, finding it almost too incredible, he nonetheless calls his wife Sarah, the new name given to remind him of the promise of God (v. 15).
6 tn Heb “the daughter of ninety years.”
7 tn Heb “the son of ninety-nine years.”
8 tn Heb “circumcised in the flesh of his foreskin” (also in v. 25).
