10 And he said, I will certainly return to thee at [this] time of the year, and behold, Sarah thy wife shall have a son. And Sarah was listening at the tent-door, which was behind him. 11 Now Abraham and Sarah were old [and] advanced in age: it had ceased to be with Sarah after the manner of women. 12 And Sarah laughed within herself, saying, After I am become old, shall I have pleasure, and my lord old? 13 And Jehovah said to Abraham, Why is this, that Sarah laughs, saying, Shall I indeed bear, when I am become old? 14 Is [any] matter too wonderful for Jehovah? At the time appointed I will return to thee, at [this] time of the year, and Sarah shall have a son. 15 And Sarah denied, saying, I did not laugh; for she was afraid. And he said, No; but thou didst laugh.
Matthew Henry's Commentary on Genesis 18:10-15
Commentary on Genesis 18:9-15
(Read Genesis 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, 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.