Charles Ellicott Commentary Genesis 18:12

"And Sarah laughed within herself, saying, After I am waxed old shall I have pleasure, my lord being old also?" — Genesis 18:12 (ASV)

Sarah laughed. See the 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, she caught their words only occasionally. Perhaps she was listening at that moment only because she heard her own name mentioned. When she heard them talk of her having a child, she naturally laughed, possibly thinking 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.”