It had been planned for close to a year. The position, its requirements, and all of its detailed protocols had been studied and reviewed numerous times. Yet when the mishkan was fully ready and Aharon was about to begin his mishkan service, he resisted. Apparently, Aharon was so emotionally unready that Hashem himself had to intercede. According to Rashi (8:2) Moshe is told, "find the words to convince him and persuade him." This conversation, though cryptic and vague, is obviously important enough to be recorded and become part of what we transmit from generation to generation.
Through various midrashim (Toras Kohanim, Shemini; Rashi 9:7) we can piece together the realities of the moment, the fears that were addressed, and the ideas that gave Aharon chizuk and courage. As Aharon was about to launch his kehuna career, he was overwhelmed with memories of the eigel hazohov. According to one record, as he looked at the mizbeach its square protruding corners morphed, in his mind, into the horns of a bull, like an eigel hazohov nightmare. We can only imagine how diminished and tortured Aharon must have felt. How could he now lead his people in the holiest of places? How could he, plagued with these memories, assume the highest tier of spiritual leadership with the sin of the eigel? Such is the heart, humility and self-awareness of genuine spiritual leadership.
Moshe, following Divine instruction does not give, declaring the words that have inspired many, לכך נוצרת - for this you were chosen." Simply put, Moshe argues, "this is your purpose in life". Who turns down that kind of clarity? Would we not all want to have prophecy tell us our purpose and destiny in life? Interestingly, Mordechai's charge to the hesitant Esther, "מי יודע אם לעת כזאת הגעת למלכות" seems to be largely another way of saying לכך נוצרת.
Yet, another way to read Moshe's argument has been suggested by several commentators, including Rav Zadok of Lublin. They read Moshe's encouragement as being, "for this humility, for this uncertainty, that is why you were chosen to be kohein gadol."
In addition to the sublime spirituality of Aharon and the profound dedication to every individual Jew, perhaps it was his ability to understand failure that prepared him for a life throughout which he would represent his people before Hashem. Possibly, his keen feelings of having disappointed all that is precious in life will help Aharon greet and raise every Jew who approaches him, even one approaching with the attendant guilt and remorse of a sin offering.
This charge to Aharon finds its way into the Purim story as well. It was the Imrei Emes, the Gerrer Rebbe who began to reestablish his chasidus in Israel immediately after the holocaust, who points to the medrashic descriptions of Esther's uncertainty. He records the account of Esther who, after being emboldened by Ruach Hakodesh to confront the king, suddenly feels robbed of that spiritual uplift. As she passed by the avoda zoro in the palace, and was apparently reminded of the past sins of her people, she became spiritually and practically weak kneed again. The Rebbe explains that at times of hester panim, feelings of spiritual diminution are indeed a call to action and leadership. Based on the Zohar, he saw them as deliberate and forceful voices from above demanding that we dig deep, find inspiration and moral compass from within, and as a result emerge to behold deservedly greater Divine assistance.
Looking for the updated version of Moshe's words to Aharon, I recall the manner in which Rav Yisroel Salanter compellingly responded to his close student, Rav Yitzchak Blazer. The teacher, impressed with the communal impact his student could have and the leadership he could offer, dispatched him to lead the Jews of St. Petersburg and become the chief rabbi of this capital city. Rav Yitzchak, untested and only twenty-five at the time, resisted and explained that he is afraid given his youth and the cosmopolitan nature of the community. To which Rav Yisroel is reported to have responded, "and who shall I send, someone who is not afraid?"