God, the prophets, and Jesus all claims: Sacrifices are not required for salvation.
So, who really invented the sacrifice system?
Example: Jeremiah 7:23-24
Isaiah 1:11
God, the prophets, and Jesus, never command or approves the sacrifice.
So, how we came up with blood, and sacrifices for salvation?
God, the prophets, and Jesus, never command or approves the sacrifice...
You will learn much about the sacrificial system in researching this question. It was not invented by man. Sources may include a Torah or a Chumash.
Coats of skins, yes. Sacrifice, I do not know.Genesis 3:21 KJV
(21) Unto Adam also and to his wife did the LORD God make coats of skins, and clothed them.
There's the first sacrifice. Animals had to be slain to provide man with coats of skins, but they did not need those coats before they sinned.
The faithful offered sacrifices before the Law, such as Noah’s burnt offerings after the flood Genesis 8:20-21. The Law details Sin, Trespass, Burnt, Peace, Meal and Drink Offerings. All of these are typical, pointing forward to the crucifixion, death and resurrection of Jesus, the Lamb of God, the perfect sacrifice, who takes away the sin of the world. We become associated with this death and resurrection through belief and baptism into Jesus.There is no single command from God, the prophets or Jesus stating sacrifices of any creatures blood will give you salvation or wipes your sins.
God already said, he had nothing to do with it.
An interesting question is if God ever commands or approves of sacrifice.
That brought to mind:
Hebrews 10:12 But this man, after he had offered one sacrifice for sins for ever, sat down on the right hand of God;
Amen.
His own blood.