Our Gemara on Amud Aleph discusses two related physiological phenomena that today we do not recognize or understand well.  If a man was not able to ejaculate his seed with force similar to shooting an arrow, he was considered to be infertile.  Additionally, the woman was able to perceive this internally and her testimony on this was given more credence than the husband’s awareness or lack thereof.

Based on this way that sexuality was understood and experienced in the ancient world, the Shalah (Torah Shebksav, Vayera, Torah Ohr 45) offers a creative derash to explain Sarah’s initial laughing and denial in response to the news that she was going to give birth to a son.  I will do my best to give over this complex derasha, which shows the exegetical prowess and depth of the Shalah.

The Shalah begins with noticing a number of textual and theological difficulties with the narrative.  The text is as follows (Bereishis 18:9-11):

וַיֹּאמְר֣וּ אֵׄלָ֔יׄוׄ אַיֵּ֖ה שָׂרָ֣ה אִשְׁתֶּ֑ךָ וַיֹּ֖אמֶר הִנֵּ֥ה בָאֹֽהֶל׃ 

They said to him, “Where is your wife Sarah?” And he replied, “There, in the tent.”

וַיֹּ֗אמֶר שׁ֣וֹב אָשׁ֤וּב אֵלֶ֙יךָ֙ כָּעֵ֣ת חַיָּ֔ה וְהִנֵּה־בֵ֖ן לְשָׂרָ֣ה אִשְׁתֶּ֑ךָ וְשָׂרָ֥ה שֹׁמַ֛עַת פֶּ֥תַח הָאֹ֖הֶל וְה֥וּא אַחֲרָֽיו׃ 

Then one said, “I will return to you next year,*next year Heb. ka-‘et ḥayyah; cf. Gen. 17.21; 2 Kings 4.16–17. and your wife Sarah shall have a son!” Sarah was listening at the entrance of the tent, which was behind him.

וְאַבְרָהָ֤ם וְשָׂרָה֙ זְקֵנִ֔ים בָּאִ֖ים בַּיָּמִ֑ים חָדַל֙ לִהְי֣וֹת לְשָׂרָ֔ה אֹ֖רַח כַּנָּשִֽׁים׃ 

Now Abraham and Sarah were old, advanced in years; Sarah had stopped having her periods.*her periods Heb. ’oraḥ ka-nashim, lit. “the way of women”; 

וַתִּצְחַ֥ק שָׂרָ֖ה בְּקִרְבָּ֣הּ לֵאמֹ֑ר אַחֲרֵ֤י בְלֹתִי֙ הָֽיְתָה־לִּ֣י עֶדְנָ֔ה וַֽאדֹנִ֖י זָקֵֽן׃ 

And Sarah laughed to herself, saying, “Now I am withered, am I to have enjoyment—with my husband so old?”

וַיֹּ֥אמֶר יהֹ אֶל־אַבְרָהָ֑ם לָ֣מָּה זֶּה֩ צָחֲקָ֨ה שָׂרָ֜ה לֵאמֹ֗ר הַאַ֥ף אֻמְנָ֛ם אֵלֵ֖ד וַאֲנִ֥י זָקַֽנְתִּי׃ 

Then ה said to Abraham, “Why did Sarah laugh, saying, ‘Shall I in truth bear a child, old as I am?’

הֲיִפָּלֵ֥א מּה' דָּבָ֑ר לַמּוֹעֵ֞ד אָשׁ֥וּב אֵלֶ֛יךָ כָּעֵ֥ת חַיָּ֖ה וּלְשָׂרָ֥ה בֵֽן

Is anything too wondrous for Hashem?I will return to you at the same season next year, and Sarah shall have a son.”

וַתְּכַחֵ֨שׁ שָׂרָ֧ה ׀ לֵאמֹ֛ר לֹ֥א צָחַ֖קְתִּי כִּ֣י ׀ יָרֵ֑אָה וַיֹּ֥אמֶר ׀ לֹ֖א כִּ֥י צָחָֽקְתְּ׃

 Sarah lied, saying, “I did not laugh,” for she was frightened. Came the reply, “You did laugh

1. How could it be that Sarah was doubting God's ability to grant a miracle?
2. Additionally, why did she not laugh earlier in chapter 17:16,19, when a similar prophecy was given?  Though those earlier prophecies were private to Avraham, it is not logical that he would have withheld the good news that could have brought Sarah relief and hope. So why did she not laugh then?
3. Verse 18:13 has Hashem reporting that Sarah said, “Is it true however, that I can still have children while indeed I am elderly?”  We never find Sarah having said that. True, our sages taught that one may lie to protect another person's feelings, as we see from God switching around Sarah’s words to focus on her aging status and not Avraham’s.  However, is it really acceptable that God should lie?  Especially over such a minor matter.  Would Avraham, at his age, really be insulted to learn that his wife considered him elderly?
4. Additionally, once Sarah was confronted by Avraham, why did she persist in her denial?  Surely she must have realized that Avraham only knew about her laughing to begin with from his prophecy.  So what did she expect to accomplish by denying Avraham’s prophecy?

Shalah answers all of these questions by weaving the story as follows:

Sarah had no problem believing in a miracle.  Her laughter was out of confusion because she saw two contradictory states within herself.  On the one hand, in certain aspects she miraculously returned to a youthful state, with smooth skin and resumption of menses (18:12).  Yet, in other ways, she still felt old in her insides, and even felt her breasts incapable of producing milk.  This is what is meant by the first part of the verse, “And Sarah laughed inwardly”, instead the term inwardly was literally about her insides.  She could not understand how God would have her both old and young at the same time.  It is one thing if God made a miracle and she fully returned to youth, or God made a miracle and despite her old age, she still would be able to conceive and carry a baby to full term as a senior citizen, but what was the sense of a combination of both?  

Sarah also saw another contradiction, that while she was restored partially to youth, Avraham was not.  According to the Midrash, when Sarah said that Avraham was elderly, she also meant he no longer could ejaculate with the force of an arrow and thus was infertile.  Since we saw in our Gemara that the husband is not always aware of this problem and the woman perceives it more accurately, Sarah was concerned that Avraham was unaware of his issue. If so, he would not adequately pray for a resolution, which would also hinder the possibility of a miracle.

In actuality, God had a plan and restored Sarah’s youth in stages.  At this point she only needed a restoration of menses to conceive, and a restoration of youthful skin so as to be attractive to Avraham and inspire him to be sexual with her with the fullest energy (yes, Shalah says that!).  A year later, after Yitschok was to be born, Sarah will have a full restoration to youthfulness so she could nurse and handle the physical stresses of labor and childcare.  That is why the verse (18:10) uses a duplicative language, “Shov ashuv, return, I shall return”, because Sarah’s restoration will happen in two stages.

According to this version of events, Sarah actually did say she was elderly as well, so God was only stating a falsehood by omission, in not mentioning Sarah’s casting aspersion on her husband’s virility. Furthermore, while Avraham thought she was doubting God greatly, he misunderstood.  Sarah was just confused why she only had a partial return to youth.  However, God still wanted Sarah to be rebuked, because it showed lack of faith and patience in a subtle way, and she should have expected that God would restore her fully at the time that it would be necessary.  Similar to how the Jews had to learn to trust God for the manna daily and not hoard it. Furthermore, Sarah was not denying that she laughed.  The verse (18:15) that describes her denial as coming out of fear was not fear of Avraham. Rather, she was saying, “I am God fearing; do not misunderstand my laughter as a lack of faith.”

Aside from just enjoying this exegetical tour de force, there are subtle lessons here to be gleaned.  Shalah sees God as economical in His use of miracles, and brought Sarah miraculously back to youthfulness only in stages, as was needed.  Along those lines, it was considered a necessity for her skin to return to youth so that Avraham would be inspired to perform intimately.  This is especially significant as this is the same Avraham who was so modest that he did not even notice that his wife was attractive until he saw her lift her clothes a bit when they had to cross a river before entering Egypt, or possibly because he had to realistically assess the risk of her being kidnapped (see Rashi Bereishis 12:11 and commentaries).  And finally, Sarah was held liable for not being patient and believing that God has a plan which would emerge in stages, even though it was odd to her that her youth was only partially restored.