ויקרא, פרק ט׳, פסוק א׳

A profound transition occurs as the period of preparing the Tabernacle ends and the actual service begins. After seven days of Moses initiating the sanctuary—putting it up and taking it down daily—Aaron and his sons officially step into their roles. The primary approach among commentators is that this milestone takes place on the eighth day of the inauguration, the first of Nisan, when the Tabernacle is permanently erected. A different perspective suggests it is the eighth day of the month of Nisan [אבן עזרא, תורה תמימה בשם ר' עקיבא]. The choice to highlight the number eight is deeply symbolic. While the number seven represents the natural, mundane world, eight signifies a step into the supernatural and the holy. Because of this, matters of the sanctuary, the priestly garments, and the sacrifices frequently revolve around the number eight [רבנו בחיי, כלי יקר].

This pivotal day is marked by a sharp contrast between immense joy and deep sorrow. On one hand, it was a day of profound celebration before God, likened to the day the world was created. It was distinguished by ten special honors, such as being the first day of the priesthood and the first time fire descended from heaven [רש״י, מזרחי, רבנו בחיי]. On the other hand, a persistent thread of sadness runs through the events. Commentators explain this sorrow in two ways. First, tragedy strikes with the death of Aaron's sons, Nadab and Abihu, teaching that there is no perfect joy in this world. Just as great leaders throughout history faced disaster at the height of their happiness, so too did Aaron and his wife Elisheba on the day the Tabernacle was dedicated [אור החיים, רבנו בחיי, צאינה וראינה]. Second, the sadness belongs to Moses himself. On this day, he watched the High Priesthood pass from him to his brother and his descendants forever. This was a consequence of Moses resisting God's mission for seven days at the burning bush [אור החיים, שפתי כהן].

Despite his personal sorrow, Moses acts with extraordinary greatness of spirit. Standing outside the Tent of Meeting, he calls Aaron and his sons out to instruct them on the sacrifices [אבן עזרא, ביאור יש״ר]. This call is a formal summons to greatness. Moses tells Aaron that just as Aaron had genuinely rejoiced in Moses' rise to leadership during the Exodus from Egypt, Moses now rejoices in Aaron's appointment as High Priest [רבנו בחיי, דעת זקנים, הרא״ש]. Setting aside his own feelings, Moses operates swiftly, with perfect order, and in full public view to transfer the sacred responsibility to his brother [אור החיים].

Moses also summons the elders of Israel to witness the event, serving several important purposes. Primarily, he wants to make the appointment entirely transparent. By having the elders present, Moses proves to the nation that Aaron is becoming High Priest by a direct command from God, rather than seizing power or benefiting from family ties [רש״י, מזרחי, גור אריה]. Another approach suggests that the elders are called simply to honor them on this festive day when the Divine Presence comes to rest among the people [העמק דבר, הרא״ש]. Furthermore, the elders have a practical role. Because the sacrifices offered that day are meant to atone for the nation's past sins—specifically the Golden Calf and the selling of Joseph—the elders, as representatives of the congregation, must stand over the offerings and lean their hands upon them [כלי יקר, חזקוני, בכור שור]. Moses deliberately calls only the elders, rather than the entire nation, to maintain the privacy of this atonement, ensuring that the shame of the Golden Calf is not publicly broadcast [חומת אנך].