The overarching theme of the Bible is that of a perfectly loving, holy and just God creating, sustaining and redeeming His rebellious children. Because He is completely holy, He cannot allow sin into His presence (Leviticus 11:45). Because He is righteous and just, He cannot allow sin to go unpunished (1 Kings 8:32; Psalm 7:11). And because He is love (1 John 4:8), He gave His only Son to pay the punishment for our sins, so that he could shower His children with His infinite mercy and grace (2 John 1:3) and give them eternal life in His presence.
The first death occurred in the garden when God killed animals to clothe Adam and Eve with their skins (Genesis 3:21), which symbolized covering, but not removing, their sin, through shed blood. Thus began the “scarlet thread” (Joshua 2:18) of redemption by the blood woven throughout Bible history. The shedding of animal blood for sacrifices commanded by God covered the sins of His people, but only temporarily (Leviticus 4; 3-7).
Not until the perfect Sacrifice of Jesus Christ Himself would believers be washed clean in His blood (Revelation 1:5), their sins removed as far from them as is the East is from the West (Psalm 103:12). through His completed work on the cross.