“And I will bless her, and give thee a son also of her: yea, I will bless her, and she shall be a mother of nations; kings of people shall be of her.”
King James Version (KJV)
17:15 Sarah shall her name be - The same letter is added to her name that was to Abraham's. Sarai signifies my princess, as if her honour were confined to one family only: Sarah signifies a princess, viz. of multitudes.
17:17 Then Abraham fell on his face, and laughed - It was a laughter of delight, not of distrust. Now it was that Abraham rejoiced to see Christ's day, now he saw it and was glad, #John 8:56|, for as he saw heaven in the promise of Canaan, so he saw Christ in the promise of Isaac, and said, Shall a child be born to him that is an hundred years old? - He doth not here speak of it, as at all doubtful, for we are sure he staggered not at the promise, #Rom 4:20|, but as wonderful, and that which could not be effected but by the almighty power of God.
17:18 And Abraham said, O that Ishmael might live before thee! - This he speaks nor as desiring that Ishmael might be preferred before the son he should have by Sarah, but as dreading lest he should be forsaken of God, he puts up this petition on his behalf. The great thing we should desire of God, for our children, is, that they may live before him, that is, that they may be kept in covenant with him, and may have grace to walk before him in their uprightness. God's answer to this prayer, is an answer of peace. Abraham could not say he sought God's face in vain.