Moses comforted Aaron and his sons over the death of Nadav and Avihu. Even though it is normally forbidden for a priest who is in mourning to officiate, Moses instructed Aaron and his two surviving sons to continue with the sacrificial service – including eating their designated portions of the sacrifices – as an exceptional case.
Eliciting the Supernatural
וַאֲכַלְתֶּם אֹתָהּ . . . כִּי כֵן צֻוֵּיתִי: (ויקרא י:יג)
[Moses said to Aaron and his sons,] “You must eat [your portions of the sacrifices . . . ] for so have I been commanded [by G‑d].” Leviticus 10:13

The normal rules governing the behavior of the priests were suspended on the eighth day of the installation rites because the day’s essential message was that G‑d can override His own rules. Whereas the number seven signifies the natural order, the number eight signifies the miraculous transcendence of natural order.

Nevertheless, there could not have been a miraculous eighth day of the Tabernacle’s inauguration without the preceding seven non-miraculous days. This is because G‑d makes His miraculous intervention in life dependent upon us.

The ultimate transcendence of the natural order will occur in the Messianic era. The miraculous revelations of the future will be the result of the preparations we make now. As we continue to refine the world through natural means, we should bear in mind that the results of our efforts will be beyond whatever we can imagine.1