“And no man shall be in the Ohel Moed when [the Kohain Gadol] comes into the Holy to atone, until he leaves...” (Vayikra 16:17)
Immediately after Aharon’s sons, Nadav and Avihu, died for offering an unbidden offering, Hashem commanded Moshe to direct Aharon on the rituals of the Yom Kippur service, when he would be able to approach Hashem in a closer manner than any other time. Once a year, the Kohain Gadol would enter the Holy of Holies and offer incense there.
When he went in no one else was allowed to be present. Not only non-Kohanim, but even Kohanim weren’t allowed to be there. However, it didn’t stop there. The Yerushalmi in Yoma says that even those “who resemble people,” as it says in Yechezkel that the holy chayos (angels) had faces like the faces of men, were not allowed to be present when the Kohain Gadol went in to serve Hashem.
“How glorious was the Kohain Gadol!” says Rabbeinu Bachya, “with this great attribute that even the holy angels cleared a place for him to serve the King one-on-one.” What does it mean that the angels cleared a place for him? Angels don’t take up space. They are imperceptible to human senses. Why would they need to vacate the Bais HaMikdash when the Kohain Gadol was doing his avoda?
Nadav and Avihu died trying to come close to Hashem. People could mistakenly come to the conclusion that there’s a barrier preventing us from becoming too close to Him. Therefore, even though Yom Kippur was months away, Hashem gave these commandments now, lest anyone get the wrong idea and think this was true. He wanted us to know just how close we can truly get.
Man has the chance to become so close to Hashem on an individual basis that even angels cannot intervene. Yes, it has to be on Hashem’s terms, following His guidelines, but far from putting up a barrier, Hashem gives us a guidebook to come closer to Him.
He loves each one of us for who we are in our own unique way, and we each have our special service which we alone can offer. This is the lesson of Achrei Mos, to know that Hashem loves us and wants us to get closer to Him. So much so, in fact, that He could not wait to let us know that this is what He desires from us, and Hashem gave us step-by-step instructions on how to do it.
