In Parashat Tetzaveh, Hashem designates Aharon and his descendants to serve as the Kohanim (Shemot 28:1). The ensuing Pesukim (28:2-29:43) describe the Bigdei Kehunah, the clothing for the Kohanim. Why was Aharon, not Moshe Rabbeinu, appointed as the Kohein Gadol? As the leader of Am Yisrael, Moshe appears to have been be the obvious candidate for the role of Kohein Gadol. What can we learn from the fact that Aharon led the Jews spiritually while Moshe led the Jews in regard to material matters?
To explain why Aharon was appointed as the Kohein Gadol, we must look at the Gemara (Zevachim 102a), which cites Rav Shimon bar Yochai’s opinion that Moshe Rabbeinu should have been the Kohein Gadol, but he lost the opportunity when he objected to Hashem at the burning bush (Shemot 4:14-16). According to this Gemara, Moshe was the Kohein Gadol until Aharon and his children became the Kohanim forever.
According to most Meforashim, however, Moshe was never supposed to be the Kohein Gadol. Why was Moshe denied the job of being the Kohein Gadol? Ibn Ezra (28:1 s.v. VeAtah) believes that Moshe was not the Kohein Gadol for a practical reason – because Moshe was so busy as the leader of the Jewish people, he simply did not have the time to also be the Kohein Gadol. Malbim (ad loc. s.v. VeAtah Hakreiv Eilecha) writes that different jobs require different skills, and Hashem thought that Aharon was more suited for the job. The Dubno Maggid, a Chassidic master, believes that the job of the Kohein Gadol is to educate and lead the Jews by example. Moshe could not fulfil the job of being a role model for the Jews because he was considered to be on a higher level than the average Jew. Aharon, on the other hand, related to all Jews and therefore was more suitable for the job. Both Malbim and the Dubno Maggid believe that the reason Moshe did not become the Kohein Gadol was that Aharon was more qualified for the job.
To explain why Moshe and Aharon were each given their roles, we must analyze their personalities. Moshe is known as a person who always sought the truth. Aharon, on the other hand, is known as a person who always sought peace. Hashem’s decision to make both Moshe and Aharon leaders of the Jews teaches us that a good leader is one who is strict at some times and lenient at other times.