Leviticus 9:22-24 (KJV)
22 And Aaron lifted up his hand toward the people, and blessed them, and came down from offering of the sin offering, and the burnt offering, and peace offerings.
23 And Moses and Aaron went into the tabernacle of the congregation, and came out, and blessed the people: and the glory of the Lord appeared unto all the people.
24 And there came a fire out from before the Lord, and consumed upon the altar the burnt offering and the fat: which when all the people saw, they shouted, and fell on their faces.
Leviticus 9
The Huge Undertaking Of Animal Sacrifices
There was a purpose for animal sacrifices. It was in preparation for the Lamb of God, who would come to take away our sins.