The Day of Atonement:

The Day of Atonement occurred only once a year Leviticus 16:34. The high priest could not go behind the veil into the Most Holy Place of the temple whenever he chose.  In fact, two sons of Aaron, the first high priest, were instantly killed when they did not follow the precise instructions set by God.  Since no sinful person could stand in the presence of God and live, the high priest needed to take special precautions.  Aaron would bathe himself with water and put on simple sacred garments.  These garments reflected his unworthiness and humility for not only himself but also for the people he represented.  Even the tabernacle needed to be cleansed in order for the holy God to dwell among a sinful people since it had been contaminated by the sins of the people.

The high priest would begin this significant day with blood sacrifices of animals.  The shedding of blood was necessary to make atonement for Israel’s sins.  There was no other way.  A bull would first be sacrificed for the sins of the high priest and his family Leviticus 16:11.  Then, two goats were presented and lots were cast to determine their fate.  The goat whose lot was not chosen was sacrificed and its blood was sprinkled on the atonement cover for the sins of all people.