Why is Hashem so insistent that Moshe Rabeinu be the one to go to Mitzrayim and lead Bnei Yisrael to redemption? Moshe's argument that Aharon be the one to go seems to make a lot of sense: Aharon had been with the people in Mitzrayim, unlike Moshe who had to flee and was out of contact with them; Aharon was a great communicator; Aharon was a "rodef shalom" and had the personality for the job. Why did G-d reject the obvious choice and demand the Moshe himself go?
On Jan 1 we had the pleasure of hearing a shiur from Rav Aharon Kahn in which he explained that the choice of Moshe was necessary as it served to define our unique concept of freedom. In America, by way of analogy, we a Declaration of Independence and a Constitution. Tzvey dinim, if you will. The Declaration of Independence states our grievances with King George and says we are free. But freedom in the Declaration has no boundaries -- there is no system of law, there is no framework of a government. It was only years later that the colonies came together to create the Constitution and establish a framework of law so that they could function together as a nation. The concept of freedom and the concept law, with its restrictions, are two totally separate ideas.
Moshe was a man of din, Aharon of rachamim, peshara. Moshe therefore was inevitably going to be the one to bring down the Torah to Klal Yisrael. Moshe Rabeinu, G-d insisted, must therefore also be the man to lead Klal Yisrael out of Egypt. Unlike the American system, the secular system, where freedom and law stand apart, in Judaism freedom and law are inextricably linked.
"V'zeh lecha ha'os ki anochi shilachticha -- ta'avdun es ha'Elokim al ha'har ha'zeh." The meforshim are all bothered: how could mattan Torah, which would only happen weeks after yetzi'as Mitzrayim, serve as a sign for the people to believe Moshe? Rav Kahn suggested that Hashem was not giving Moshe a sign to present to Klal Yisrael. He was giving Moshe a sign, an explanation, for himself personally. "LECHA ha'os" -- like in the parsha of tefillin, where Chazal darshen "lecha l'os -- v'lo l'acheirim" with respect to tefillin shel yad -- "ki anochi shilachtiCHA," why YOU, and not Aharon or anyone else is being sent. The reason is "ta'avdun es ha'Elokim al ha'har ha'zeh," because you Moshe are the vehicle through which mattan Torah will take place. Therefore, you must also be the vehicle by which geulah from Mitzrayim takes place. The two must go hand in hand.
There is no break between our Declaration of Independence and our Constitution. We go from being avadim of Pharoah to being servants of Hashem, bound to his law. "Ain lecha ben chorin elah ha'osek baTorah." This is our unique approach -- freedom and law are intertwined.
This is the argument on Pesach night between the rasha and the chacham. The rasha argues, "Mah ha'avodah ha'zos lachem?" It's the holiday of freedom -- why are you bothering me with all these halachic details? Freedom means I can do what I want. But the chacham's approach is "ain maftirin achar ha'pesach afikoman" -- freedom means halacha. Freedom means law.