Laughter

Why is Yitzchak named for laughter?  Why is Yitzchak able to open up the wells that Avraham had dug but the Phlishtim closed up?  Why is it ליצני הדור, as Rashi says, that deny Avraham's birth of Yitzchak?  Why are they called ליצנים?  Why is it that Yizchak is seen מצחק את רבקה אשתו?   

When Sarah sees Yishmael מצחק she says he has to go.  Similarly, after the sin of the agel the possuk says ויקמו לצחק.  Why are those acts of צחוק negative but the צחוק of Yitzchak is positive?  

What is the nature of צחוק?  The word צחוק can be split into צא חוק, to leave the natural order.  The middah of צחוק is to be able to go outside the boundaries of the normal order of things.  Entertainment, משחקים, is a way of escape.  It is a way of leaving the natural grind of life and escaping to a false existence.  The middah of צחוק can be negative when one leaves the order of morals, of a healthy way of life, and turns to sin.  When צחוק is positive it is used to bring a higher existence into the normal order.  This is the צחוק associated with Yitzchak.  This is a צחוק which only becomes ultimately realized at the end of the story.  

The middah of Yitzchak, of gevurah seems at odds with צחוק, it would seem the polar opposite?  But it is actually gevrah that leads to צחוק.  The wells of Avraham, the middah of chesed, are counterbalanced by the Pelishtim who are the embodiment of the tumah of chesed.  The Pelishtim are able to close up the influence of the positive chesed of Avraham with chesed of tumah.  The middah of Yitzchak, of gevurah, is to be able to bring out the capabilities from within a person and that was not able to be removed by the Phlishtim.  The ability to bring out dormant powers, to bring out kedusha from where it does not seem to be capable to exist is the middah of צחוק.  To be able to access kedusha where there would seem to be nothing there, to be able to access a higher level, is the middah of צחוק in the positive.    

The Sefer Yetzirah associates the middah of צחוק with Adar for Adar is the time when things seemed totally bleak.  Haman saw it as the month when Moshe Rabbenu died, it the last month of the year, a time which seems dead and bleak.  However, it is also the month of the birth of Moshe.  From the darkness ,unexpectedly, comes a time of great light and joy.  The opposite of what things seemed at first blush is the ultimate joke, the צחוק.   

This is why the life of Yitzchak is constantly being seen through the prism of צחוק.  The ליצנים don't want the power of laughter to be used for the positive, they wish to highjack it for the negative and could not accept that the legacy of Avraham would live on through Yitzchak.  Their claim was that Avraham's only son is Yishmael who is מצחק is a sinful matter.  That is the leztanut.  They wish to use this middah of צחוק not as a way of illuminating the world but as a way of darkening the world.  They claim that Yishmael has inherited the middah of צחוק and that they are not bound by Avraham's teachings of ethics and morals (based upon shiur of Rav Avraham Shwab, and "Looking Into The Sun" chapter on laughter, see also Tzitkas Hataddik #260.)

Letzanim

Rashi at the beginning of the parsha says the Torah repeats Avraham begot Yitzchak since שהיו ליצני הדור אומרים מאבימלך נתעברה שרה וכו'. מה עשה הקב"ה? צר קלסתר פניו של יצחק דומה לאברהם, והעידו הכל - אברהם הוליד את יצחק, וזהו שכתב וכו' שהרי עדות יש שאברהם הוליד את יצחק.  Why are they called ליצנים presumably they are reshaim for saying lashon harah?  Furthermore, if they didn't believe someone so old could give birth they should have claimed Sarah couldn't give birth for Avraham already showed he could have a son, for he had Yishmael?  The Beis Halevi says that they were not denying who the parents were, there claim was why did Sarah only give birth now, at such a late stage of life, it must be the fact that she was taken by Avimelech and she had to endure that pain was a merit for her to have a child, וזהו שאמרו בדרך ליצנות מאבימלך נתעברה שרה וכמו הליצנות שאומרים פלוני בנה בית מחמאה, והכוונה שע"י שעשה סחורה בחמאה והרויח ממון בנה הבית, וע"כ קראם ליצני הדור.  This was the ליצנות.  However, since in time the point would be lost and people would take it literally that Yitzchak is a son of Avimelech, ויהיה לעז חלילה וע"כ צר קלסתר פניו כשל אברהם.  

His grandson, the Briskor Rav, takes a different lesson from the Rashi:

In the Mir parsha sheet, Rav Chayim Shmuelevitz is quoted as having said as to why the letzanim would claim Avraham is out of the picture and not Sarah, that one can not a question on a letz.  Presumably, he means that if one wants to scoff at something they will do so even if a non-sensible manner.  One can't debate a letz with logic. 

Rav Ezrachi asks why does a miracle have to occur just to debunk the claim of letzanim?  He explains that the point isn't just to prove the letzanim wrong.  Rather, Avraham's mission in life is to get people to come closer to Hashem.  If they don't believe in the continuity of Avraham, they are in denial of his mission and that will bother Avraham.  It is the fact that there are letzim unconvinced by Avraham that demands a miracle in order to make Avraham happy. 

The Rebbe asks why would Yitzchak not look like Avraham in the first place if he is his biological son?  He explains the middot of a person are reflected in their countenance and since Avraham is chesed and Yitzchak is din they would have looked different (Likutay Sichos volume 20, 30.)  

Prayer Of Distress Prayer Of Mincha

וְיִצְחָק֙ בָּ֣א מִבּ֔וֹא בְּאֵ֥ר לַחַ֖י רֹאִ֑י וְה֥וּא יוֹשֵׁ֖ב בְּאֶ֥רֶץ הַנֶּֽגֶב וַיֵּצֵ֥א יִצְחָ֛ק לָשׂ֥וּחַ בַּשָּׂדֶ֖ה לִפְנ֣וֹת עָ֑רֶב וַיִּשָּׂ֤א עֵינָיו֙ וַיַּ֔רְא וְהִנֵּ֥ה גְמַלִּ֖ים בָּאִֽים

וַיְהִ֗י אַֽחֲרֵי֙ מ֣וֹת אַבְרָהָ֔ם וַיְבָ֥רֶךְ אֱלֹהִ֖ים אֶת־יִצְחָ֣ק בְּנ֑וֹ וַיֵּ֣שֶׁב יִצְחָ֔ק עִם־בְּאֵ֥ר לַחַ֖י רֹאִֽי

Why do we need to be informed of Yitzchak's presence in באר לחי ראי?  

The name באר לחי ראי originates from when Hagar is sent away by Sarah and the malach appears to her and says she will have Yishmael.  The possuk says וַתִּקְרָ֤א שֵׁם⁠־י״י֙ הַדֹּבֵ֣ר אֵלֶ֔יהָ אַתָּ֖ה קל ראי.  Onkelus says she was praying to Hashem and refering to Him as the one who sees all.  The Targum Yonasan adds דחמי ולא מתחמי, the One who sees but is not seen.  The next possuk says  עַל⁠־כֵּן֙ קָרָ֣א לַבְּאֵ֔ר בְּאֵ֥ר לַחַ֖י רֹאִ֑י.  Rav Hirsch notes the addition of the word לחי to include all of time and the change in vowel from Hagar saying רֳאִ֑י to רֹאִ֑י to indicate Hashem sees every person, He sees me at all times.  The spot of באר לחי ראי is the place where Hagar prays to Hashem.  It is a place she designated for prayer.  The Seforno says that is why Yitzchak chose that as his place to pray for it was already designated as a place of prayer. Rav Hirsch notes the strange phrase בָּ֣א מִבּ֔וֹא, "he came from coming," indicates that he felt the need, he was drawn to באר לחי ראי to pray for his own match as this was the place that the family has heard am message from Hashem beforehand in the case of Yishmael, and now he was coming home from being drawn to באר לחי ראי.  The next possuk, וַיֵּצֵ֥א יִצְחָ֛ק לָשׂ֥וּחַ בַּשָּׂדֶ֖ה, Chazal identify as Yitzchak praying.  However, the line also demonstrates the difference between the prayer of Hagar and that of Yizchak.  

Hagar prays to Hashem in times of great distress.  However, as the Targum Yonasan says, she doesn't see Hashem in other words, she is not always cognizant of His presence in her life.  In times of upheaval she calls out to Hashem.  Rashi says Yitzchak went to באר לחי ראי in order to bring Hagar so that Avraham could marry her again.  Hagar still lives in באר לחי ראי, that is her world view.  

At the Akedah it says וַיִּקְרָ֧א אַבְרָהָ֛ם שֵֽׁם⁠־הַמָּק֥וֹם הַה֖וּא י״י֣ ׀ יִרְאֶ֑ה אֲשֶׁר֙ יֵאָמֵ֣ר הַיּ֔וֹם בְּהַ֥ר י״י֖ יֵרָאֶֽה.  Avraham didn't merely acknowledge that Hashem sees us but ה יראה, will be seen.  We see Hashem.  As the Gemarah Chagigah (2a) says יראה יראה כדרך שבא לראות כך בא ליראות מה לראות.  Avraham and his descendants don't just know of Hashem's presence but they see Hashem as part of their life.  This is what is represented by the mincha prayer of Yitzchak.  It is not the beginning or end of the day where it is more understandable to start out the day with a prayer or bookend with a prayer when one is not tarried, it is the prayer in the middle of the day.  In the midst of one's activities, one recognizes the Hand of Hashem in one's activities.  וַיֵּצֵ֥א יִצְחָ֛ק לָשׂ֥וּחַ בַּשָּׂדֶ֖ה.  This is a mere שיחה not in the context of a more formal prayer yet even in such a situation Yitzchak prays to Hashem.  Yitzchak transforms prayer into an integral part of one's activities (based upon Mimamakim by Rabbi Mandelbaum, post of Rabbi Rudman.) 

(The Kli Yakar says that the prayer of mincha is readily accepted because it is in the middle of the day removed from the time of night which is strive judgement.  Rav Shmuel Eliyahu takes the opposite approach.  He explains that mincha is compared to ketores, תִּכּוֹן תְּפִלָּתִי קְטֹרֶת לְפָנֶיךָ מַשְׂאַת כַּפַּי מִנְחַת עָרֶב (Tehillim 141:2)  because just as ketores has the ability to nullify strict judgement as seen when Aharon was told to use ketores to heal the nation, so too the prayer of mincha has the ability to nullify the time of strict judgement which is present in the afternoon.)

Potential and Actualization

The Gemarah Bava Bathra (16b-17a) says שלשה הטעימן הקב"ה בעולם הזה מעין העולם הבא אלו הן אברהם יצחק ויעקב אברהם דכתיב ביה בכל יצחק דכתיב ביה  מכל יעקב דכתיב ביה כל.  How does the word כל reflect the idea that the Avos received a taste of the next world in this world?  In the order of the sefirot reflected in the possuk לך ה הגדולה the word kol appears כי כל בשמים וארץ to refer to yesod .  As the possuk indicates, the word כל means the place of connection between heaven and earth.  In other words, it refers to the capability of joining heavens and earth.  שמים means the ruchni and ארץ is the gashmi. The Avos were able to bring the ruchni into the gashmi.  That is what it means they had a taste of the next world in this world and that is the middah of כל.   

ואברהם זקן בא בימים וה' ברך את אברהם בכל.  This beracha of כל is after Avraham is old.  The word זקן the Gemarah says means זה שקנה חכמה.  The זקן has already acquired, he has reaped the benefits of life.  A young person is full of untapped potential, they are open to endless possibilities.  The older one gets the amount of possibilities becomes less but the possibilities in a life spent right have been accessed and utilized properly.  In a larger form this is the idea of תוהו and תיקון.  The beginning of the world was תוהו וחושך.  As the Ramban says, the first creation was the undefined היולי which contains the basic matter, the potential for all form but it has not been actualized.  The potential is accessed through creation. In other words, this is the same idea as the separation between שמים וארץ.  The earth is the basic land mass on which things happen, it is the area of potential.  The heavens is when that potential is accessed, the ruchni, that is created.  That is why the idea of זקן, of using one's potential, is the combination of heaven and earth and hence Avraham is given כל, the ability to taste olam habah in this world.  

This concept is hinted to in the מערת המכפלה in Chevron. The word Chevron is like the word חיבור for connection.  The doubled cave in Chevron means the מערת המכפלה represents the meeting point of heaven and earth.  That is why Avraham is determined to buy it.  This is the only recorded purchase in the Chumash done with כסף, money.  Money is something which in it of itself doesn't have value ,tis value is its purchasing power, in its ability to obtain something else.  The actualization of the power of money is in a purchase.  That is why the the place of connecting heaven of earth, of the actualization of potential must be purchased through money, through כסף. 

The Rambam says (Melachim 9:1) עַל שִׁשָּׁה דְּבָרִים נִצְטַוָּה אָדָם הָרִאשׁוֹן ... נִמְצְאוּ שֶׁבַע מִצְוֹת. וְכֵן הָיָה הַדָּבָר בְּכָל הָעוֹלָם עַד אַבְרָהָם. בָּא אַבְרָהָם וְנִצְטַוָּה יֶתֶר עַל אֵלּוּ בְּמִילָה. וְהוּא הִתְפַּלֵּל שַׁחֲרִית. וַיִּצְחָק הִפְרִישׁ מַעֲשֵׂר וְהוֹסִיף תְּפִלָּה אַחֶרֶת לִפְנוֹת הַיּוֹם. וְיַעֲקֹב הוֹסִיף גִּיד הַנָּשֶׁה וְהִתְפַּלֵּל עַרְבִית. וּבְמִצְרַיִם נִצְטַוָּה עַמְרָם בְּמִצְוֹת יְתֵרוֹת. עַד שֶׁבָּא משֶׁה רַבֵּנוּ וְנִשְׁלְמָה תּוֹרָה עַל יָדוֹ.  What does it mean וְנִשְׁלְמָה תּוֹרָה?  The Avos demonstrated the great potential of a person.  They were not bound the exact details of the mitzvot but were able to grow in a manner that they saw fit.  Moshe Rabbenu added the finishing touches, the mitzvot which are given to us a the guide to lead to perfection.  Rashi at the beginning of Chumash asks why does the Torah start from בראשית ברא and not החודש הזה?  According to the Rambam we can answer that the base of the Torah is reflected in the parshios of the Avos.  The mitzvot come to fortify and set lines and boundaries for the yesod of the Aovs which is that one is here to be fully access their potential but the basics are reflected by the Avos.  That is what Chazal say חייב אדם לומר מתי יגיעו מעשי למעשי אבותי, they don't say one must do all the mitzvot but try to act like the Avos, meaning to bring to fruition one's capabilities.  

יפה שיחתן של עבדי אבות יותר מתורתן של בנים.  The gematria of Eliezer, the עבדי אבות is 318 = שיח.  The שיח of Eliezer reflected the essence of Eliezer, of his inner essence (see Meor Vashemesh Lech Lecha.)  שיח means the growth of the ground.  Eliezer took his potential and grew (all of this is based upon a shiur by Rav Moshe Shapira.) 

Beyond Understanding

Rashi says when Hashem told Avraham to do the akedah he used the terminology of נא, as a request because "[God] said to him, “I beg of you, pass this test for Me, so that people will not say that the first ones [tests] had no substance."  Even if Avraham did not pass the test of the akedah, why would that invalidate his passing all of his previous tests?  If a person gets a score of 90% on a test, does the 10% that he missed invalidate the fact that he got 90% right?  If Avraham did not pass the test of the akedah, maybe he wasn't good enough to pass that test but that doesn't invalidate his passing of the earlier tests? 

There are two parshios devoted to Avraham, parshas Lech Lecha and Vayerah.  The first parsha, Lech Lecha, is a command to leave his geographical homeland and move to Eretz Yisrael.  This command is not a mere command to change locations but to change his entire outlook in life.  He leaves behind his idolatrous upbringing and finds his own service of Hashem.  This service of Hashem is based upon Avraham's understanding.  All the tests Avraham had to pass, although a challenge, were challenges that did not run counter to the entire philosophy of Avraham.  He was challenged to run against his comfort zone, but he could justify his actions to his followers.  

The test of the akedah however was not something that made sense at all in the worldview of Avraham.  How could he, a man who preached understanding, sacrifice his own son.  Avraham has no way of justifying his actions to the world.  He is forced to do something which runs counter to his logic.  This is the test that proves Avraham is really serving Hashem merely for the sake of serving Hashem.  The point of the tests is to test the boundaries of Avraham's commitment.  The tests prove that Avraham's commitment to Hashem is boundless.  However, If he fails the test of the akedah, it is not that his commitment to Hashem goes only 90% of the way and he just missed the last 10%, it means that his service of Hashem only goes so far as his intellect allows it to go.  It means that his entire service of Hashem does not stem from complete commitment to Hashem, but is limited and dictated by his own understanding.  The failure proves that Avraham's commitment is limited by the boundaries of his own mind which shows that the tests he did pass was also only since it made sense to him but not that they were acts of true commitment to Hashem.  It is the akedah that is the litmus test to prove if Avraham is serving Hashem because it fits within Avraham's world or is he serving Hashem purely to serve Hashem (Likutay Sichos volume 20 sicha 3.) 

The Midrash recounts an argument between Yitzchak and Yishmael if getting a bris at 13 years old like Yishmael is better or getting one at 8 days like Yitzchak is better.  It is understandable the argument of Yishmael since he had to choose to go through the pain but why does Yitzchak claim that an 8 day bris is better?  The bris milah is the act of the covenant between Hashem and Klal Yisrael.  If one gets a bris milah due to one's choice it means the bris is limited to one's understanding.  To demonstrate that there is an innate connection to Hashem, not limited to one's understanding, one gets a bris at the first possibility (Likutay Sichos volume 25 sicha 3.)  It is due the bris milah that Avraham gets the ability to have a connection to Hashem beyond his own understanding and can pass the test of the akedah.  Pre-milah Avraham is receives prophesy only as a means of communication as a necessary means of communication.  Post- milah וירא ה אליו, Hashem came merely to visit Avraham, to "hang out" with Avraham.  Avraham's connection to Hashem is not limited to a means to communicate, to do something else, it is an innate connection which in which Hashem comes to visit Avraham purely to experience being with Avraham. 

Delayed Shacharis

Rambam Tefillah (3:1) rules תפילת השחר - מצותה, שיתחיל להתפלל עם הנץ החמה; וזמנה, עד סוף שעה רביעית שהוא שליש היום. ואם עבר או טעה והתפלל אחר ארבע שעות עד חצי היום - יצא ידי חובת תפילה, אבל לא יצא ידי חובת תפילה בזמנה: שכשם שמצות תפילה מן התורה, כך מצוה מדבריהן להתפלל אותה בזמנה שתיקנו לנו חכמים ונביאים.  There are different interpretations as to the understanding that one may pray shacharis after 4 hours until chatzos.  Either this is the law of tashlumin, a law that R' Yehuda that holds one may pray only untill 4 hours agrees בדיעבד there is a concept of praying until chatzos, (see Beis Yosef siman 89,) or it is a new law of a cheftah of prayer שלא בזמנו (see shiur of R' Willig.)  

According to the peshat the Beis Yosef (siman 89) favors and the peshat of the Lechem Mishna there is a concept of prayer after 4 hours even according to R' Yehuda.  Where does that come from?  If R' Yehuda limits the time of the prayers to when the tammid was actually offered why would there be room to daven until chatzos? 

As noted in the past, the Rambam rues both of tefillot being in place of korbanot and that they were established by the avot. The rule of praying until 4 hours is is tefillah is patterned after the korbanot and the times Chazal gave to pray are patterned after the korbanot.  However, the actions of the avot exit to give three basic times to the framework of prayer, morning, afternoon and night.  Hence, even though the timeframe of tefillah to correspond to the korban is lost after the 4^th hour of the day, the fact that it is still morning allows one to pray as a tefillah corresponding to the prayer of Avraham.  That aspect remains to allow one to pray שלא בזמנו and still get a kium of tefillah to parallel that of Avraham.  

The New Avraham

The maftir of Noach says וַיִּקַּ֨ח אַבְרָ֧ם וְנָח֛וֹר לָהֶ֖ם נָשִׁ֑ים שֵׁ֤ם אֵֽשֶׁת⁠־אַבְרָם֙ שָׂרָ֔י וְשֵׁ֤ם אֵֽשֶׁת⁠־נָחוֹר֙ מִלְכָּ֔ה בַּת⁠־הָרָ֥ן אֲבִֽי⁠־מִלְכָּ֖ה וַֽאֲבִ֥י יִסְכָּֽה.  Rashi says יסכה – [זו שרה, על שם]⁠א שסוכה ברוח הקודש, ושהכל סוכין ביופיה, ולשוןב נסיכות, כמו: שרה לשון סררות.  Sarah is identified in the possuk with two names, יסכה and שרי in the same possuk.  Why is she called by two names in the same possuk?  And why is the name יסכה alluding to her ruach hakodesh spelled out here and never again and why not mention it in the context of Hashem acknowledging the greatness of her prophesy?  

The second to last possuk in Noach says וַיִּקַּ֨ח תֶּ֜רַח אֶת⁠־אַבְרָ֣ם בְּנ֗וֹ וְאֶת⁠־ל֤וֹט בֶּן⁠־הָרָן֙ בֶּן⁠־בְּנ֔וֹ וְאֵת֙ שָׂרַ֣י כַּלָּת֔וֹ אֵ֖שֶׁת אַבְרָ֣ם בְּנ֑וֹ וַיֵּצְא֨וּ אִתָּ֜ם מֵא֣וּר כַּשְׂדִּ֗ים לָלֶ֙כֶת֙ אַ֣רְצָה כְּנַ֔עַן וַיָּבֹ֥אוּ עַד⁠־חָרָ֖ן וַיֵּ֥שְׁבוּ שָֽׁם.  The parsha of Lech Lecha opens  וַיֹּ֤אמֶר י״י֙ אֶל⁠־אַבְרָ֔ם לֶךְ⁠־לְךָ֛ מֵאַרְצְךָ֥ וּמִמּֽוֹלַדְתְּךָ֖ וּמִבֵּ֣ית אָבִ֑יךָ אֶל⁠־הָאָ֖רֶץ אֲשֶׁ֥ר אַרְאֶֽךָּ.  What is the nature of these two travels?

The Ramban asks why are we not introduced to Avraham as a tzaddik but instead are merely introduced to him as a man told to leave his home?  The Maharal (Netzach Chapter 11) explains that we are being taught that Avraham is not chosen merely because he is a tzaddik and hence if future generations are not so righteous they will no longer be chosen, rather we are chosen by Hashem because he desires to choose Avraham and his children no matter what state they are in.  

Parshas Lech Lecha is when Avraham is chosen to be a sperate nation apart from everyone else.  The last possuk in Noach says Terach died.  Rashi notes that Terach didn't actually die at that point but Terach is dead to Avraham when he starts his journey to Lech Lecha.  In other words, at this point Avraham is no longer connected to Terach, he is starting his own legacy (see Gur Aryeh.)  Originally, Terach also was going to travel to Eretz Yisrael, he also was on the path to being able to transform his life and be the patriarch for the Abraham clan . However, he never is quite able to complete his journey, he gets stuck in Charan.  The Terach life is the life of the idol worshipers, who, as the Rambam explains, started with noble intensions to serve the messengers of G-d but they got lost along the path and never ended up completing the journey of reaching to Hashem.  They got stuck on the road with the emissaries.  Avraham sees beyond the forces in the world, he sees the True Master, Hashem and seeks Him out.  He is able to get to the end of the path that was embarked on the by idol worshipers.    

Rashi (end of Noch) says that Avraham was thrown into a fire by Nimrod for rejecting idols and after he survived and Haran was given the choice between Hashem and the idols he also chose Hashem and he was thrown into the fire and perished.  Rav Moshe Shapira explains it wasn't merely that Haran was  hedging his bets and that he would choose what seemed better after seeing the results for Avraham.  The act of Haran was a reflection of his nature.  His was not a trailblazer, a man able to forge his own way, like Avraham.  This is why Avraham is the first of the Avos.  Haran wanted to know the truth an then he would stick to it faithfully, no matter the circumstances.  Haran is the father of the אמהות.  He is the father of Sarah, the grandfather of Rachel and Leah, and the father-in-law of Lot, who leads to Rus and the Messianic line.  The trait of Haran is the trait of the imahot, to see the truth and stick to it no matter how hard it is. 

The ability of Sarah to be Yisca, to be a great prophetess, stems form the misaras nefesh of Haran.  His acknowledgement of the truth to the ability that he gave his life for it yielded the ability for his offspring to cling to Hashem even in the darkest places.  It is due to her being the daughter of Haran, that Sarah is Yisca, that she has such spiritual clarity of vision.  Hence, when she is mentioned  as a daughter of Haran her name is Yisca, for it is the relationship with Haran that makes her Yisca.  It is her role as the daughter of Haran that makes her Yisca.  But in her role as the wife of Avraham, the starter of a new nation, no longer connected to the past, her relationship to her father is not mentioned, her essence is being Sarah, the wife of Avraham, the matriarch of Klal Yisrael (see Gur Aryeh end of Noach, based upon article by R' Yehoshua Shapira, יסכה זו שרה – פרשת נח.)  

The Sarah and Avraham of Parshas Noach were part of the greater Terach family.  They where members of a family which started seeking the truth but didn't follow through.  In Lech Lech, Avraham and Sarah are a new dynasty, no longer connected to the past.  All relationships to past self identities, children and grandchildren of Terach, Yisca etc. are removed and they embark upon a journey of Lech Lecha, of self exploration to find their own way, their own destiny.