The sin offering: regulations (4:1-35)
Burnt offerings, cereal offerings and peace offerings were not compulsory; people made them voluntarily to express their devotion. The sin offering, however, was compulsory whenever people realized they had committed some (accidental) sin that broke their fellowship with God. In the other offerings there was an element of atonement (for sin affects everything that people do), but in the sin offering, atonement was the central issue.
The animal was killed in the usual manner and again the richest and most vital parts were burnt on the altar as God’s portion. The special feature of the sin offering was the treatment of the blood and the carcass. In the case of sin of the high priest (4:1-12) or of the whole nation (13-21), some blood from the sacrifice was poured out on the altar and some was taken into the Holy Place, where it was sprinkled in front of the veil and placed on the horns of the altar of incense. This was to show that approach to God, previously hindered through sin, was possible again, because atonement had been made. After this the carcass was burnt outside the camp. When people saw this being done, they knew that the ritual was over: sin had been judged and fellowship with God was restored.
In the case of a private person (in contrast to the case of the high priest or the whole nation), the animal’s blood and carcass were treated differently. The place where the priest met with God, and where the nation met with God through him, was in the Holy Place at the veil that hung between the altar of incense and the ark of the covenant. Therefore, the blood was applied there, to symbolize that through the blood of atonement access to God was possible again (see v. 6-7). But for ordinary people, the place of meeting with God was the altar in the court where they offered their sacrifices. The blood was therefore applied to this altar, to symbolize atonement and renewal of fellowship with God (22-35).
No blood from the sin offering of a private person was taken into the Holy Place, and the carcass, instead of being destroyed outside the camp, was eaten solemnly by the priests. The worshipper would have assurance that God was satisfied and fellowship restored when he saw the same priest who offered the sacrifice on his behalf eating part of it in the presence of God. The priest was allowed to eat the sacrificial meat in this case, because the sin offering was not for his own sin. He could not do so when the sin offering was for his own sin or for the sin of the nation of which he was a member (6:24-29).
A simple rule summarized the procedure for the treatment of the carcass and the blood. In those cases where the blood was brought into the Holy Place, the carcass had to be burnt, not eaten. In those cases where the blood was not brought into the Holy Place, the carcass had to be eaten, not burnt (6:30; 10:18).