(12) Sarah laughed.--See Note on Genesis 17:17. The laughter of both husband and wife brings into prominence the inconceivable character of the fact. Sarah's conduct has been very unjustly condemned. Though Abraham may have begun to guess that his visitors were more than men, she probably had no such suspicions. Sitting inside the tent, and catching their words only occasionally, listening, perhaps, now only because she heard her own name mentioned, when she hears them talk of her having a child she naturally laughs. thinking possibly that they did not know how old she was.

After I am waxed old.--The Hebrew word is stronger and more lively. It means "to be worn out like an old garment."

Verse 12. - Therefore (literally, and) Sarah laughed within herself - Abraham had laughed in joyful amazement, (Genesis 18:17) at the first mention of Sarah s son; Sarah laughs, if not in unbelief (Calvin, Keil, 'Speaker's Commentary,' Wordsworth), at least with a mingled feeling of doubt and delight (Lange, Murphy) at the announcement of her approaching maternity - saying, After I am waxed old shall I have pleasure, my lord being old also? - literally, and my lord, i.e. my husband, is old. The reverential submission to Abraham which Sarah here displays is in the New Testament commended as a pattern to Christian wives (1 Peter 3:6).

18:9-15 Where is Sarah thy wife? was asked. Note the answer, In the tent. Just at hand, in her proper place, occupied in her household concerns. There is nothing got by gadding. Those are most likely to receive comfort from God and his promises, who are in their proper place, and in the way of their duty, Lu 2:8. We are slow of heart to believe, and need line upon line to the same purport. The blessings others have from common providence, believers have from the Divine promise, which makes them very sweet, and very sure. The spiritual seed of Abraham owe their life, and joy, and hope, and all, to the promise. Sarah thinks this too good news to be true; she laughed, and therefore cannot as yet find in her heart to believe it. Sarah laughed. We might not have thought there was a difference between Sarah's laughter and Abraham's, ch. 17:17; but He who searches the heart, saw that the one sprung from unbelief, and the other from faith. She denied that she had laughed. One sin commonly brings in another, and it is not likely we shall strictly keep to truth, when we question the Divine truth. But whom the Lord loves he will rebuke, convict, silence, and bring to repentance, and if they sin before him.Therefore Sarah laughed within herself,.... Not for joy of a son, and as pleased with it, believing so it would be; but as disbelieving it, and perhaps deriding it, and confuting it with a laugh, which, though it did not appear in her countenance, was secretly in her heart:

saying, not with her mouth, but in her mind:

after I am waxed old, being almost ninety years of age:

shall I have pleasure? in conception, or rather in having a son, and in suckling and nursing him, and bringing him up; for in bearing and bringing forth is sorrow:

and my Lord being old also; which increased the difficulty and her unbelief: the Apostle Peter seems to have respect to this in 1 Peter 3:6.