And Sarah laughed to herself, saying, “Now that I am withered, am I to be rejuvenated? Furthermore, my husband is old.” Hashem said to Avraham, “Why did Sarah laugh, saying, "Shall I in truth bear a child, but I am old?"
The Ohr Hachaim asks two questions. 1) We learn in Parshas Lech Lecha that Avraham also laughed when Hashem informed him that he will have a child. Why did Hashem only express his displeasure with Sarah and not Avraham? 2) Why did Sarah magnify her surprise and disbelief by mentioning that her husband is old?
The Ohr Hachaim answers these questions in two steps. First, he suggests that Sara's laughter was not an expression of mockery or disbelief. Her laughter was a pure and true expression of joy and faith similar to that of her husband Avraham. She even expanded her praise by acknowledging the double magnitude of this miracle by noting that her husband was old. But now the question is only magnified, why then would Hashem express his disappointment in her?
The Ohr Hachaim presents a novel idea and uniquely interprets the Posuk. Hashem was disappointed as to why it took Sarah so long to believe in His promise that she would have a child. He complained that Sarah only believed in the miracle and expressed her thanksgiving after her body was rejuvenated. It was only after she witnessed that miracle did she believe that the other miracle of having a child would also occur. In contrast, Avraham believed in Hashem's promise immediately. There was no delay. He accepted Hashem's promise as a fact. He believed that he would have a child even without any sign or indication whatsoever.
