Gordon Moyes, pastor of Wesley Mission in Sydney, Australia, said in a recent sermon:
"Taking life, even to eat, is never a trivial thing. God tells Moses: "For the life of a creature is in the blood, and I have given it to you to make atonement for yourselves on the altar; it is the blood that makes atonement for one's life." (Leviticus 17:11)
"The word translated "atonement" means to "make an atonement to make reconciliation."
"Reconciliation" expresses the result of an atoning sacrifice. To comprehend the basics of sacrifice, let's look carefully at a sacrifice for purification from sin by a common person. When anyone is guilty in any way, he must confess in what way he has sinned and, as a penalty for the sin he has committed, he must bring to the Lord a lamb or goat from the flock as a sin offering; and the priest shall make atonement for him for his sin. Leviticus 5:5-6 "If he brings a lamb as his sin offering, he is to bring a female without defect. He is to lay his hand on its head and slaughter it for a sin offering at the place where the burnt offering is slaughtered. Then the priest shall take some of the blood of the sin offering with his finger and put it on the horns of the altar of burnt offering and pour out the rest of the blood at the base of the altar. He shall remove all the fat, and the priest shall burn it on the altar on top of the offerings made to the Lord by fire. In this way the priest will make atonement for him for the sin he has committed, and he will be forgiven." Leviticus 4:32-35
"From this analysis of a sacrifice for sin I see several principles: confession or acknowledgement of sin is a necessary part of the sacrifice. A sacrificial animal is costly to the sinner. Forgiveness is not free. There is a close identification between the sinner and the sacrifice. The imparting of sin by the laying on of hands suggests that the animal becomes a substitute for the sinner. Killing the animal is very personal. It is not done for the sinner but by the sinner himself. So our sins can be forgiven, but only at a cost that is borne by another."
(You can read the entire sermon by going to http://www.wesleymission.org.au/ministry/sermons/030323.asp)