"And the Lord spake unto Moses after the death of the two sons of Aaron, when they offered before the Lord, and died;
And this shall be an everlasting statute unto you, to make an atonement for the children of Israel for all their sins once a year. And he did as the Lord commanded Moses."
The Lord has Aaron came into the holy place and perform specific acts in order to atone for his sins and the sins of his family, and the sins of all of Israel. As I went through these acts I wept. I could feel how broken heart Aaron must have felt. How serving the Lord would have healed his soul and comforted him. I know going to the temple when I grieve has done this for me. What a loving thing the Lord did for Aaron. No wonder this is called the Day of Atonement.