Hashem remembered the extraordinary empathy that Rachel Imeinu manifested for her sister’s plight. Lest she be discovered as Leah, Rachel gave her the predesignated signs that Yaakov Avinu (sensing that Lavan would pull off such a stunt) had originally given to her. Rashi explains that now that she was aware that she was barren, Rachel feared that Yaakov would divorce her, and she would be compelled to marry Eisav. (This is based upon the commentary that quoted people as saying that Lavan had two daughters, and his sister Rivkah Imeinu had two sons; the older son (Eisav) would marry the older daughter [Leah] and the younger son [Yaakov] would marry the younger daughter [Rachel]. Since Leah was married, however, if Rachel were to find herself divorced, she would have to marry Eisav. Furthermore, Rachel prayed that she be able to participate in the creation of Am Yisrael. Finally, after much fervent prayer, Hashem’s desire for the prayers of the righteous was satisfied and Rachel was able to conceive. Indeed, when Eisav heard that Rachel was barren, he had anticipated that Yaakov would divorce her and he could “gallantly” step in.
At this point, Leah and her shfachos, maidservants, had given birth to ten sons. The Shivtei Kah, Tribes of Hashem, the foundation of the future Klal Yisrael, was almost complete. Imagine Rachel’s anxiety. With each new birth in the family of Yaakov, the chances of Rachel becoming a Matriarch in Klal Yisrael was reduced. It was almost over. At the last moment, Hashem “remembered.” What was it that He remembered? It was the simanim, signs, that Rachel gave Leah, the very same signs that enabled Leah to become a Matriarch and to be progenitress to six of the shevatim, tribes.
Let us go back in time and play out the scenario without Rachel’s empathy for her sister. Leah would have gone to the chupah and, sometime later when Yaakov would have asked for the simanim, Leah would have been unable to produce them, Yaakov would have become quite upset and Leah would have been mortified. Yaakov would have made a ruckus and he would have married Rachel.
Rachel, however (as Horav Yitzchak Zilberstein, Shlita, observes), would have been barren, since the only reason that she became pregnant with Yosef and Binyamin was the merit of conceding the simanim. Otherwise, Rachel would have continued to be barren.
Rachel’s act of selflessness, her empathy and love for her sister, not only earned her a place in the creation of Klal Yisrael as one of its Matriarchs, but we also find in the Midrash that it was specifically because of this z’chus, merit, that Hashem allowed Klal Yisrael to return to the Holy Land after the destruction of the Bais Hamikdash. Yitzchak Avinu prayed and beseeched Hashem to employ his willingness to be sacrificed as a z’chus for Klal Yisrael. Hashem said it was not sufficient. Then Rachel came forward and asked that He might accept the z’chus of her vitur, concession, giving up everything, her entire future for which she had passionately prayed – just so that her sister would not be humiliated. Can you imagine the awesomeness of this z’chus?
Horav Chaim Kanievsky, Shlita, derives from here that vitur – the ability to concede to another, to dash one’s hopes of becoming a mother in Klal Yisrael, to transcend one’s inner feelings, just so that her sister not become humiliated – is even greater than the Akeidas Yitzchak!
After all, what greater act of sacrifice exists than the ability to renounce one’s future so that her sister not be shamed? Giving up that for which one has waited a lifetime is a greater act of devotion than relinquishing one’s life.