Why God commanded animal sacrifices for forgiveness of His people in the Old Testament.
Jesus killed the first animals in the Garden of Eden.
Killing innocent animals was the “first edition” of God’s plan of salvation. The Father viewed the killing of animals (done rightly) as a sort of down payment for the future and real sacrifice of Jesus to cover our sins.
Old Testament people found God’s forgiveness in the sacrifices, though only Jesus’ blood had the power to bring real atonement. We should not be ashamed of the Old Testament sacrifices.