Parshas Acharei Mot begins with G-d telling Moshe to tell Aaron after the death of his sons not to just walk into the adobe of G-d and then moves on to a discussion of the Yom Kippur service. What is the relationship between these two things, the death of Aaron's sons and Yom Kippur? Earlier, Aaron's sons had committed a sin. They had died. This seems like the natural order of things. A grievous enough sin leads to death. But instead G-d informs Moshe and Aaron of Yom Kippur, and beyond it, of the larger idea that G-d forgives sins. And that this is a major function of the Kohen. The priesthood is not meant for personal aggrandizement. The Kohen should not simply feel free to make himself at home in G-d's house. Or to take arrogantly take on privileges as if he were entitled to them. He is there to represent the people before G-d. And this is the function of the Kohen Gadol on Yom Kippur. He asks G-d for forgiveness for their sins. At the root of the death of Aaron...