Why does the Torah insert the word "u'Keshartam le'Os al Yadecha"?
Refer to 13:9:1:1 & 13:9:1.1:1 and notes.
What are the connotations of "al Yadecha"?
Rashi (in Sh'mos 13:9): In Sh'mos 13:9, it is written with a 'Hey', so it can be read 'Yad Keiheh', to teach us that it is worn on the weak (left 1 ) arm 2 next to the heart. 3
Hadar Zekenim: If one's right hand is weaker, he puts it on one's right arm. Targum Yonasan in Bo Sh'mos, 13:9, learns from "Al Levavecha" that one lays Tefilin on the left arm (and not on the hand).
Menachos 37a: Others there learn this either from the Pasuk in Yeshayah, 48:13 "Yadi Yasdah Eretz ve'Yemini ... " or "u'Keshartam" from "u'Chesavtam" - just like one writes Tefilin with the right hand, so does one bind them on the left arm - next to the heart. Refer to Sh'mos, 13:9:3.1:1*.
As the Gemara in Menachos, 37a learns from the fact that the Pasuk in Eikev, 11:18 writes in the same Pasuk as the Mitzvah of Tefilin "Vesamtem es Devarai Eileh al Levavchem".
Whereabout on the left arm does one place the Tefilin shel Yad?
Refer to Sh'mos, 13:9:1:1 and note.
Seeing as in Bo Sh'mos, 13:9, the Torah writes "Vehayu le'Totafos ... " (plural), why does it writes here "Vehayah l'cha le'Os" (singular)?
Refer to Sh'mos, 13:9:1.2:1.
Why does the Torah refer to the Tefilin Shel Rosh as "Totafos"?
Rashi (citing Sanhedrin, 4a): The Caspian word 'Tat' and the African word 'Pas', both of which mean 'two' - hinting at the four Parshiyos in the Tefilin Shel Rosh. 1
And each is in its own box, which explains why it is written only about the Tefilin Shel Rosh, but not about the Tefilin Shel Yad, where all four Parshiyos are written on one piece of parchment and placed inside one box.
What is the meaning of "Bein Eineicha? Where exactly is the Tefilin shel Rosh worn?
Refer to 13:19:5:1 and notes.
Menachos, 37a: Above the hairline.- the area where the brain of a baby is soft, which we learn from a Gezeirah Shavah "Bein Einechem" "Bein Einechem" from 'Korchah' in Re'ei, 14:1. 1
See Torah Temimah in Bo Sh'mos, 13:9, note 41.
What are the implications of the phrase "Vehayu (plural) le'Totafos bein Einecha"?
Menachos, 36a: It implies that, as long as one is wearing the Tefilin shel Rosh "between the eyes" one should be wearing two Tefilin - in other words one should always remove the Tefilin shel Rosh first. 1
See Torah Temimah, note 45.
Having taught the Mitzvah of Tefilin in Parshas Bo, why does the Torah repeat it here?
Ramban (on Pasuk 7): In order a. to add the obligation of tying the Tefilin to one's arm and b. to hint at the knot of the Tefilin - which the Chachamim learn from a Halachah le'Moshe mi'Sinai.
Tosfos (Sanhedrin 4b DH 'Tat'): The Torah mentions Tefilin in four places, and they constitute the four Parshiyos that are placed inside the Tefilin.
Why does the Torah juxtapose Mezuzah to Tefilin both here and in Eikev, 11:20?
Oznayim la'Torah: Because they represent "be'Chol Levavcha" - Tefilin shel Yad which are bound beside the heart; "be'Chol Nafsh'cha" - Tefilin shel Rosh. "be'Chol Me'odecha" (with all your money (property) - "be'Chol Me'odecha". 1 Laying Tefilin and affixing a Mezuzah to one's doorpost enables a person to love Hashem with all his heart, with all his Neshamah (thoughts) and with all that he owns. 2
