Parashat Shemini begins by describing the momentous period for Aharon and his sons of the dedication of the Mishkan. On Rosh Chodesh Nisan, the first day of service in the Mishkan, there was a tragic incident that resulted in the deaths of two of Aharon's sons. What quality did Aharon have that enabled him to thrive in his work in the Mishkan while two of his sons, Nadav and Avihu, died before the first day was completed?
A few pieces of introduction are needed in order to answer this question. The first is found in Parashat VaYikra, the first place the Torah speaks about a leader bringing a Korban Chatat. The Pasuk there states, “Asher Nasi Yecheta,” "When a prince will sin" (VaYikra 4:22). When the Nasi sins, he should bring a Korban Chatat. The obvious question here is why the Torah expects the Nasi to sin. (The language of “when” implies this.) In the cases of the entire nation and the Kohein sinning, the terminology “Asher” is not used; what about a leader makes him more prone to sin than others? Wouldn’t he be the best role model and furthest from sin? Rashi answers, based on the Sifra, that this is actually a term used to praise the Nasi. Fortunate is the generation, he says, whose leader is careful to bring Korbanot to repent for the sins that he did unintentionally, for he will surely bring Korbanot to repent for those he did intentionally. This helps us answer a question raised on a Pasuk found in Sefer Yechezkeil. There it describes that the Nasi, which in context could mean the Mashiach, has to bring a Korban Chatat (45:21). The Toldot Ya’akov Yosef (commenting on BeReishit 38) tells us that the Mashiach ben David is one who is an “Ani Rocheiv Al Chamor,” a poor man riding a donkey. Riding on a donkey is a humbling act, and the Mashiach chooses to ride something simple and low to the ground. The Pasuk in Yechezkeil says that the Nasi (Mashiach) has to be one who is humble and can admit his faults, able to publicly bring a Korban for his sins.
The second piece of introduction is found at the very end of Mesechet Sotah. The last Mishnah discusses how, at Rabi Yehuda HaNasi's death, humility and fear of heaven disappeared. Later, the Gemara ends by quoting the statements from Rav Nachman and Rav Yosef, who say that Rabi Yehuda HaNasi should not be connected to the termination of these character traits, for they themselves are the true embodiment of these qualities. These statements are very puzzling. How can they say these things about themselves if they really wish to be viewed as having the qualities that they describe? It certainly does not sound like a humble act. The valuable lesson that can be learned from this Gemara is that humility does not mean suppressing oneself to the point of his saying that he is useless and not valuable. The person who is humble is aware of his strengths, his weaknesses, and is mindful of the true source of his accomplishments.
In Parashat Shemini, when the Torah discusses the actions of Nadav and Avihu, they are referred to as “Bnei Aharon.” Rav Shamson Refa’el Hirsch learned from this phrase that they died because they were arrogant. Nadav and Avihu knew that they were special, as they were eligible to work in the Mishkan. When they entered the Mishkan, they wanted their own divine revelation, since they thought the revelation that the entire nation experienced was insufficient for children of Aharon such as themselves. This arrogant attitude clearly showed that they missed the point and they were killed for it. For this, the Torah emphasizes that they were special only because they were “Bnei Aharon,” not for their own deserving. They forfeited their right to individual greatness with their arrogance. Aharon, on the other hand, was very different. He realized that he was the leader only because Hashem recognized his greatness and felt that he was worthy to be leader. Aharon was a leader with the humility that his children lacked.
Rav Yosef Dov Soloveitchik once explained why Aharon’s Korban Chatat was a young bull and not the regular goat. A goat is stubborn in nature and is therefore fitting as a retribution for most individuals. That was not Aharon’s weakness, however. A young bull often times follows his mother without any resistance. Aharon, not wanting to cause any more bloodshed, allowed Bnei Yisrael to create the Eigel without any resistance, and thus had to make this Korban to repent. Hashem was trying to alert Aharon to his weakness and mistakes, and tell him that he needed to be the spiritual leader of Bnei Yisrael. At times, he may not be perfect, but having a leader that makes mistakes is better than no leader at all.