Why does the Torah write "ha'Yom ha'Zeh"?
Rashi: To teach us that every day Hashem's Mitzvos should be considered new as if they had been given on that day. 1
Ramban: Because Moshe completed teaching all the Mitzvos to Yisrael on that day. 2
Seforno: It is written in connection with the new covenant that Yisrael were about to enter into, 3 whereby Hashem ordered them to do His Chukim and Mishpatim - in order to do good to them, and they took upon themselves to carry them out.
Megilah, 20b: The Torah juxtaposes "ha'Yom ha'Zeh" to the Parshah of Viduy Ma'asros to teach us that the entire day is eligible for Viduy Ma'asros. 4
Refer to 26:16:151:1.
Even though the Mitzvos of Hakhel and writing a Sefer Torah are written only later (PF).
The B'ris of Arvos Mo'av.
See Torah Temimah, note 52.
What are the implications of the second part of the Pasuk - "Veshamarta Ve'asisa Osam ... "?
Rashi: They are the words of a Heavenly Voice, which proclaimed - 'You brought the Bikurim today; you will bring them again next year!' 1
Seforno: It refers to the Chukim and Mishpatim, which Hashem commanded 'to guard and to keep them ... '.
See Sifsei Chachamim, as to why Rashi deviates from the simple explanatiion..
What are the connotations of "be'Chol Levavcha"?
Rosh: It means that, when one Davens to Hashem, one should not have two hearts (issues on one's mind)
See also Ba'al ha'Turim.
What are the connotations of "u've'Chol Nafshecha"?
Refer to 6:5:5:1-3. With reference to the previous answer, it means to do so with such conviction that one's personal desires cannot turn one away. 1
See also Ba'al ha'Turim.
QUESTIONS ON RASHI
Rashi writes that "ha'Yom" teaches us that every day we should consider Hashem's Mitzvos as new. But we already learned this in Keri'as Shma "Asher Anochi Metzavecha ha'Yom" (Va'eschanan, 6:6)?
Moshav Zekenim: One might have thought that the Pasuk there applies exclusively to Keri'as Shma. The current Pasuk teaches us that applies to all Mitzvos. 1
Oznayim la'Torah: The Torah repeats it here, because following Devarim, Ve'schanan and Eikev, which comprized Divrei Musar, Moshe repeated many of the Mitzvos that he already taught, or new Mitzvos that, for some reason he did not present until now - in Re'ei, Shoftim, Ki Seitzei and part of Ki Savo. Now that he completed the Mitzvos and was about to refert to Divrei Musar, it was appropriate to insert this lesson here.
Moshav Zekenim: This is difficult, seeing as there the Pasuk is also discussing all the Mitzvos!
