Parshat Mishpatim

Shemot 24:7 (Avivah Zornberg trans.)
“All that God has spoken we shall do and we shall hear!”
Rashi interprets the ratification of the covenant occurring in chapter 24 as occurring before the giving of the Ten Commandments. This is strange — why does Rashi (and his sources in the Midrash) do this?
Rashi argues, in his reordering of the chronology, that Moses has told the story of Genesis and the seven Noachide laws prior to the Sinai Revelation. It is this historical retelling by Moses that the people are ratifying in chapter 24.
Avivah Zornberg
The newness of the Sinai moment is, indeed Rashi’s subject. … Before the Torah is given, Moses renarrates to them the “old laws,” the “old story” from Creation to the present — but in a newly sacralized form. … [it is] newly infused with a sense of relationship to God, the Creator, who desires these modes of behavior. … If the people can commit themselves to a new relation even with these “rational” laws, then they are qualified to receive the specific Revelation of Sinai.
In Rashi’s reading, what the people are saying is, “We reaffirm the old laws and our historical covenants and we are ready to move forward to the new laws God will give us.”
Why might acknowledging the past and reaffirming it, be necessary to move forward? 
How might rehearing or rereading the past provide a way for transforming the future? 
Shabbat 88a (Avivah Zornberg, trans.)
When the Israelites said, “We shall do,” before “We shall hear,” six hundred thousand angels came down and attached two crowns to each Israelite, one for the doing, the other for the hearing…
When the Israelites said, “We shall do,” before “We shall hear,” there came forth a heavenly voice: “Who revealed to My children this secret that the ministering angels use? — as it is written, ‘Bless God, His angels, who are mighty of strength, and do His word, to hear the voice of His word.’ (Psalms 103:20) — first they do, then they hear.
Why might doing be necessary for hearing?
Avivah Zornberg suggests the following:
they expressed a desire to go beyond the doing mode, beyond the basic requirements of the Commandments. “We shall hear!” means that they hold themselves alert to further and finer intimations of God’s will.
They are acknowledging that they have acted in the framework of a particular cultural and historical legacy. They are allowing themselves to move forward and listen to a new understanding.
Rabbi Nachman of Breslov (Avivah Zornberg trans.)
“We shall do” — refers to the revealed — that is, to the commandments that one can fulfill, on one’s own level. “We shall hear” — refers to the hidden — that is, to things that one cannot grasp. For around each commandment, there are other things, which belong to the class of the hidden. The commandment itself one can fulfill; but the spiritual work that surrounds the commandment is largely unknown, hidden. This, too, is the relation of the Torah and prayer: the Torah can be known and fulfilled; while prayer is generated in that area that surrounds each commandment, which is enigmatic. For hearing is a function of the heart, as in Solomon’s prayer: “Give Your servant a hearing heart.” And the heart expresses itself to God in prayer.
What is Rabbi Nachman adding?