Earlier Divrei Torah on Mishpatim:
The Torah Perspective on Self-Determination. (2008)
On the Obduracy of First Impressions (2007)
The Limitations on Majority Rule (2007)
Klal Yisrael, offered the Torah, responded Na'aseh Ve'Nishma. It’s amusing to note that this statement, which refers to our commitment to learn and do mitzvos, is in Shemos 24/7. (It’s only amusing, because perek numbers are arbitrary, and because “midvar sheker tirchak is in 23:7, which should mean that you can lie one hour a day. Maybe that's for when your wife asks you how her sheitel looks on her.)
Based on the Alshich, that it is the Ahava that is mashreh the Shchina, we can also say that the Na'aseh means that we will do the mitzvos realizing that it is our privilege to do them, that they show our love and gratitude to the Ribono shel Olam. We will learn the meaning and significance of the mitzvos as a limud and as a method to advance out actions, but we will do them because Hashem told us to.
Note, please, that this was a sea change from what Klal Yisrael had been doing until now. The Avos, we are told, also fulfilled the Torah (Yoma 28b); But the Avos fulfilled the Torah because they understood their underlying reasons, and so every time they did a mitzvah, they had to decide whether under the circumstances it was the most efficient thing to do. We do something they never did (with the exception of Milah). We do Mitzvos qua Mitzvos, i.e., tzivuyim of Hashem because we accepted the obligation to follow Hashem's commandments. We did this because it is Hashem's will that we do so, and we have a natural drive to bring nachas to the One that we love. That desire for this entirely novel relationship with Hashem is expressed in Na'aseh Ve'Nishma.
When one buys a gift, or does a favor, for someone he loves, he does not stop to scrutinize the economic ramifications of his act. When one does mitzvos with this attitude, one does not do a cost/benefit analysis. This is the midda of Chanun, to do things lifnim mishuras hadin, beyond the call of duty. This, then, is like the ahava that the Malachim have.