The final moments of a great leader are often filled with sorrow, but the passing of Aaron is uniquely characterized by a peaceful transition of power and deep spiritual closure. It represents the quiet transfer of a sacred duty from father to son.
The removal of Aaron's clothing refers specifically to the sacred vestments of the High Priest, rather than his everyday attire. The primary approach among commentators is that these were the distinct, holy garments uniquely designated for him [אור החיים, גור אריה]. Ordinarily, Jewish law forbids wearing these priestly garments outside the boundaries of the Tabernacle. Therefore, wearing them up the mountain was a temporary, exceptional directive commanded directly by God [שפתי חכמים, מזרחי, גור אריה, ברכת אשר].
Moses was instructed to place these garments on Eleazar while Aaron was still alive. This was done to provide Aaron with deep comfort and joy. By witnessing his son step into his monumental role and continue his life's work, Aaron was able to depart from the world with a sense of complete fulfillment and peace [רש ר הירש, שטיינזלץ, בכור שור, אלשיך].
A natural question arises regarding what Aaron wore after his High Priest vestments were removed. One perspective suggests that Moses only took off the four additional garments exclusive to the High Priest, leaving Aaron in the four white linen garments of a regular priest, which then served as his burial shrouds [ספורנו, מלבי״ם, ברכת אשר]. Another approach maintains that Moses dressed him in specific burial shrouds that had been prepared in advance [רמב״ן, הטור הארוך]. A third, more miraculous tradition describes that as Moses removed each piece of clothing, Aaron was instantly enveloped in garments of the Divine Presence or clouds of glory, ensuring he was never left exposed for even a moment [רמב״ן, אור החיים].
The sequence of Aaron's passing is described in an unusual order, noting that he was gathered to his people before he actually died. Some explain that this sequence indicates Aaron passed away the exact moment his garments were removed [אבן עזרא, ביאור יש״ר]. Others suggest that this gathering describes a peaceful kiss of death, a serene process where the soul and the body's physical forces are calmly drawn together into one place just before the spirit departs [העמק דבר, מלבי״ם]. Alternatively, being gathered refers to Aaron entering a separate, isolated space. This ensured that Eleazar, who had just assumed the role of High Priest, would not contract ritual impurity from his father's passing [צפנת פענח].
The entire process was guided by Moses with profound gentleness and honor. Moses instructed his brother to enter the cave, lie upon the bed, stretch out his hands, close his eyes, and shut his mouth. These deliberate actions symbolized a final parting from the physical performance of commandments, worldly speech, and earthly spiritual thought. Witnessing this incredibly serene and dignified passing, Moses deeply desired such a peaceful death for himself [רש״י, שפתי חכמים, גור אריה, משכיל לדוד].
Ultimately, the connection between Aaron's passing and the priestly garments reveals a profound spiritual principle. Just as the sacred garments of the High Priest serve to bring atonement to the people, the death of the righteous similarly brings atonement to the world [תורה תמימה, ברכת אשר].