Why did Moshe read out Seifer ha'Beris to the people?
Seforno: So that Yisrael should know exactly what they are undertaking, in order not to be disillusioned later.
What exactly, does "Na'aseh Venishma" mean?
Rashi (in Shir ha'Shirim, 1:15): 'We will (do what Hashem says and) accept whatever He commands us'.
Rashbam: 'We will do (carry out) what Hashem already said, and we will hear (and carry out) what He will still command us'.
Seforno: 'We will listen with the intention of obeying His instructions'. 1
Targum Onkelos and Targum Yonasan: 'We will do what Hashem says and accept His instructions'.
Hadar Zekenim (in Pasuk 8): We will do what Hashem commands us, and we accept the Bris.
Like servants who serve their master without any thoughts of reward - like angels. See Tehilim, 103:20 (Seforno).
What is the significance of the fact that Yisrael declared "Na'aseh" before "Nishma"?
Shabbos, 88a: 'When Yisrael declared "Na'aseh" before "Nishma", 1 a Heavenly Voice announced 'Who revealed this secret to My children - a secret that the administering angels use - First they do, then they listen!' 2
Shabbos, 89b: 'When Yisrael declared "Na'aseh" before "Nishma", Hakadosh-Baruch-Hu called them "B'ni Bechori Yisrael!"
Shabbos (Ibid.): Six undred thousand angels then came and tied two crowns on to the head of each person in Yisrael - one corresponding to 'Na'aseh', and one, to 'Nishma'.
Shabbos (Ibid.): See Tehilim, 103:20.
Why, in Pasuk 3, did they first declare "Na'aseh" alone and now, "Na'aseh Venishma'?
K'li Yakar: Initially, they said "Na'aseh" because they thought that Hashem had aready told them all that He wanted to say. 1 However, when they saw that he sprinkled half the blood on the Mizbe'ach and placed half in the bowls, they wrongly assumed that Hashem was about to add more, and that Moshe would then sprinkle the other half, so they announced "Na'aseh (what He already informed us) Venishma" (what is still to come). 2
What was the 'Seifer ha'Beris'?
Rosh: It was the Torah from Bereishis until this point. 1
Rosh: Even according to the opinion that the Torah was given 'Chasumah' (only when it was finished, and not each Parshah at a time), it was not actually transcribed until the end - and from Mishpatim and onwards, Moshe received each Parshah orally.
