The statement "na'ase venishma" – "we will do and we will hear" -can be interpreted on various levels.
The first meaning, of course, is willingness.
I accept the yoke of Kingship without hesitation, I accept it consummately.
This is what na'ase, "we will do," means.
The second statement, "nishma", "we will hear," means that after having accepted the Law in general, I am now ready to hear it presented point by point.
This dual statement basically corresponds to the two types of behavior we typically engage in when we have a decision to make.
We either make decisions analytically or through a synthesis.
In an analytical decision we examine the features of a situation, and by combining them, we gradually develop a picture of a complex reality whose final shape will influence the decision we make.
On the other hand, we can accept a fundamental principle right away.
Here, we are not called upon to act immediately but rather to agree to a principle and then see which obligations derive from it.
This is the psychological side.
This decision, however, also has an ontological side, because it sheds light on the nature, or the essence, of the children of Israel.
According to the Talmud, when the people cried "We will do and we will hear," God exclaimed:
"Who revealed the secret of the angels to My children?
For it is written, 'Bless the Lord 0 His angels, mighty creatures who do His bidding, to hear the voice of His word.'
First it is said that they carry out His bidding and only then that they hear it. (Shab. 88a)
–Rabbi Adin Steinsaltz
From The "Three Pilgrim Festivals," p. 218 in The Seven Lights by Rabbi Adin Steinsaltz