The Battle between Good and Evil in the Yom Kippur Service

In parashat Acharei-Mot (Vayikra 16), the Torah describes the special service performed by the Kohen Gadol (High Priest) – a service meant to atone for the sins of the Children of Israel. The means for achieving this atonement are quite unique, and the need for them demonstrates both the importance of this service, and its difficulty. The service is performed only "once a year" – on Yom Kippur, the day that stands out from all the rest of the year by its special sanctity. A fundamental question arises from a reading of this parasha on the literal level. This is not the first time that the Torah discusses a matter of atonement for sin through sacrifice. A lengthy elaboration of this precise subject is provided at the beginning of Sefer Vayikra. So we must ask: what is missing from Parshat Vayikra? What new principle appears in our parasha that we did not read about a few chapters earlier? Parshat Acharei-Mot’s additions allow us to understand that the atonement for sin is a matter more weighty and complicated than what we are able to understand from parashat Vayikra. However, the identification of these differences brings us closer to an understanding of the message that the Torah is trying to convey through them.