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.
–Rabbi Adin Steinsaltz
In The Seven Lights, p.218, by Rabbi Adin Steinsaltz