What are the connotations of "ve'Atah"?
Rashi: Inverting the words "ve'Atah" and "Im", Hashem meant to say that if they would now accept Hashem's authority upon themselves, it would be (relatively) easy from then on - since 'All beginnings are difficult'.
Oznayim la'Torah: Refer to 19:4:2:4. However was a 'free gift' from Hashem, bringing Yisrael to a level they could not possibly have attained by themselves and which cannot possibly last, unless they now work hard on themselves to retain it.
Which covenant is Hashem referring to?
Rashi, Ramban #2 (citing Ibn Ezra) and Seforno: He is referring to the covenant that He is about to enter into 1 with Yisrael (after they declare "Na'aseh ve'Nishma" - Seforno). 2
Ramban #1: The covenant that Hashem made with the Avos - "to be for them a G-d and for their children after them". 3
See Sifsei Chachamim.
See Mishpatim, Sh'mos 24:8 (Ramban and Seforno).
See Bereishis 17:7 (Ramban).
What is the definition of "Am Segulah"?
Rashi #1, Ramban #1 and Seforno: It means 'a treasured nation', 1 inasmuch as Hashem favors Yisrael 2 over all the nations. 3
Rashi #2 (in Yeshayah, 45:19): After speaking with Yisrael favorable words, telling them in advance the rewards of Torah and Mitzvos, Hashem issued them with commandments. 4
Ramban #2 (according to Kabalah): It means 'a nation that clings to Me'. 5
Targum Onkelos and Targum Yonasan: It means that Yisrael are more beloved by Hashem than all the other nations.
As in Koheles, 2:8 (Rashi and Ramban).
As the Torah writes in Va'eschanan Devarim, 4:19, 20 and in Kedoshim Vayikra, 20:27 (Ramban).
Even though all the nations are favored over and above the rest of the creation (since mankind was the purpose of the creation, as Chazal have said in Avos, 3:18, 'Man is beloved, because he was created in the image of Hashem' - (Seforno).
Based on the Pasuk there.
See Rav Chavel's footnotes.
Why did Hashem add "ki Li Kol ha'Aretz"?
Rashi, Ramban and Rashbam: Even though the entire world belongs to Hashem, 1 Hashem chose Yisrael from among all the nations to be His nation (inasmuch as, unlike the other nations, over whom Hashem has designated celestial powers to govern them, He alone governs Yisrael - Ramban). 2
Seforno: (Refer to 19:4:3:1**). One may therefore presume that the pious among the nations are also precious in the eyes of Hashem.
Which is insignificant in the Eyes of Hashem (Rashi).
As the Pasuk states in Tehilim, 121:4 'Behold He neither sleeps nor slumbers, the Guardian of Yisrael' - and this is also what the following Pasuk means when it writes "And you will be for Me a treasure" (Ramban, citing the Mechilta).
Why does the Torah use the double expression "Im Shamo'a Tishme'u"?
Refer to 15:26:152:1-3.