Regardless of who sinned, though, the priest used the same basic process in a typical sin offering. This procedure is important to understand because it will help to explain later why two goats were used for the Day of Atonement offering. We will use the sin offering for the priest as an example of how a sin offering was performed.
First (in verse 4), the guilty party - the priest, in this case - laid his hand on the head of the sacrificial animal. This symbolized the animal taking the place of the sinner. Through the laying on of a hand, the substitute was identified, and the sin was figuratively transferred to the animal. Second, the animal was killed. Third (in verses 5-6), some of its blood was sprinkled in front of the veil of the Tabernacle. The blood did not go into the Holy of Holies, which is a critical point. Fourth (in verse 7), some of the blood was put on the horns of the golden altar (which was used for incense). The rest of the blood was poured at the base of the other, larger altar, the brazen altar. Fifth (in verses 8-10), select parts of the animal were burned on the brazen altar. Finally (in verses 11-12), the rest of the animal was burned outside the camp. The details vary a little, but the same basic procedure is carried out in each of the four scenarios listed here.
Now, remember that the blood of the typical sin offering was placed on the horns of the altar. Because of what the blood represented, it is as though the horns of the golden altar became a repository for the sins of the priests and the congregation (see Leviticus 4:7, 18). The prophet Jeremiah describes all the accumulated blood and sin:
This describes just how sinful Judah was, and God says it is like the sins are engraved on the horns of the altars. With each sin offering, another record of guilt was added to the horns. The word engraved indicates a great deal of repetition. That's a lot of sin offerings. God's prescription was an annual cleansing of the golden altar, and specifically the horns, where the defiled blood was put. But the high priest had to use blood from an animal that did not have sins transferred to it. A typical sin offering would just add more sin to the altar. Instead, undefiled blood was needed. Once a year, then, the special sin offering of atonements was made to cleanse the horns of the golden altar.
