It gives me great pleasure to apply what we have learned to explain why Rabeinu HaKadosh chose to begin the first Mishnah in Torah she’b’al peh with the mitzvah of Krias Shema (Berachos 2a): "מאימתי קורין את שמע בערבין"—from when is Shema recited in the evenings? In Pesach Einayim on the allegories in Shas (ibid.), the great Gaon Chida addresses the fact that Rabeinu HaKadosh specifically began by discussing the Krias Shema of Arvis rather than that of Shacharis. It is because he was a “nitzotz” of Yaakov Avinu who instituted tefilas Arvis.
In his sefer Ben Yehoyada (ibid.), the great Rabbi Yosef Chaim of Bavel, ztz”l, adds that the reason he specifically began Torah she’b’al peh with Krias Shema of Arvis is because Yaakov Avinu instituted the mitzvah of Krias Shema—as taught in the Midrash (B.R. 98, 3) in relation to the passuk (Bereishis 49, 2):
"הקבצו ושמעו בני יעקב. מכאן זכו ישראל לקריאת שמע. בשעה שהיה יעקב אבינו נפטר מן העולם, קרא לשנים עשר בניו, אמר להם, שמעו אל ישראל שבשמים אביכם, שמא יש בלבבכם מחלוקת על הקב"ה. אמרו לו, שמע ישראל אבינו, כשם שאין בלבך מחלוקת על הקב"ה, כך אין בלבנו מחלוקת, אלא ה' אלקינו ה' אחד. אף הוא פירש בשפתיו ואמר, ברוך שם כבוד מלכות לעולם ועד... הדא הוא שישראל משכימים ומעריבים בכל יום ואומרים, שמע ישראל אבינו ממערת המכפלה, אותו דבר שציויתנו עדיין הוא נוהג בנו, ה' אלקינו ה אחד".
Based on an incident alluded to by this passuk, Yisrael were privileged to receive the mitzvah of Krias Shema. Just before Yaakov Avinu passed away, he summoned his twelve sons. He asked if any of them had a personal quarrel with HKB”H. They replied in unison, “Hear O Yisrael, our father, just as you have no quarrel with HKB”H, neither do we; rather, Hashem is our G-d, Hashem is the one and only G-d!” At that point, Yaakov Avinu also proclaimed, “Blessed is the name of His glorious kingdom for all eternity.” . . . Commemorating this event, Jews proclaim, every morning and every night, “Hear O Yisrael, our father, from the Cave of Machpeilah, that which you commanded us, we still observe: Hashem is our G-d, Hashem is the only One.”
By combining the teachings of the Gaon Chida and the Ben Yehoyada, we learn that Rabeinu HaKadosh—a “nitzotz” of Yaakov Avinu—began Torah she’b’al peh with the mitzvah of Krias Shema of Arvis, because Yaakov Avinu instituted both tefilas Arvis and Krias Shema. It is fitting to add another pertinent fact. Regarding the forty days and nights that Moshe Rabeinu was in the heavens to receive the Torah, the Midrash Tanchum teaches (Ki Sisa 36): How did Moshe know when it was daytime? In this manner: When HKB""H would teach him Torah she’b’chsav, he knew that it was day; and when He would teach him orally, Mishnah and Talmud, he would know that it was night. Therefore, Rebbe began Torah she’b’al peh, which HKB”H taught (Moshe) at night, with the mitzvah of Krias Shema of Arvis, which is recited at night.
