Leviticus 4:32-35

"'"If he brings a lamb as his sin offering, he shall bring a female without blemish".'"

"'"Then he shall lay his hand on the head of the sin offering, and kill it as a sin offering at the place where they kill the burnt offering".'"

"'"The priest shall take some of the blood of the sin offering with his finger, put it on the horns of the altar of burnt offering, and pour all the remaining blood at the base of the altar".'"

"'"He shall remove all its fat, as the fat of the lamb is removed from the sacrifice of the peace offering. Then the priest shall burn it on the altar, according to the offerings made by fire to the Lord. So the priest shall make atonement for his sin that he has committed, and it shall be forgiven him".'"

(An odd choice to proceed Revelation, but it's important to understand the laws and rules of the old covenant. The Lord did make these laws after all.)