In the Old Testament, the sin offering dealt with the forgiveness of sins and restoration of relationship with God. The priest would lay hands on the head of the animal. This would in effect transfer his sins to the beast. As the throat was slit and the life blood ran out, guilt was transferred. The act depicts the awful procedure required to free one from the guilt of their sins.
This was a picture of things to come when Jesus would give His life for the forgiveness of sins of the whole world. His sacrifice, however, is perfect. It only happened once and is eternal. The sacrifice of animals had to happen over and over again. These sacrifices merely foreshadowed what was to come.
Hebrews chapter 7:25 Wherefore he is able also to save them to the uttermost that come unto God by him, seeing he ever liveth to make intercession for them. 7:26 For such an high priest became us, [who is] holy, harmless, undefiled, separate from sinners, and made higher than the heavens; 7:27 Who needeth not daily, as those high priests, to offer up sacrifice, first for his own sins, and then for the people's: for this he did once, when he offered up himself. 7:28 For the law maketh men high priests which have infirmity; but the word of the oath, which was since the law, [maketh] the Son, who is consecrated for evermore.
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