In the original perfect environment substitution seemed unknown.
Adam did not even seem to think of giving himself for Eve. We don't see anything given in exchange for anything else yet. It seems the human race had no need for trade, exchange or substitution until this instance.
"And when the woman saw that the tree was good for food, and that it was pleasant to the eyes, and a tree to be desired to make one wise, she took of the fruit thereof, and did eat, and gave also unto her husband with her; and he did eat." - Genesis 3:6 KJV
Adam just joined Eve.
"Unto Adam also and to his wife did the LORD God make coats of skins, and clothed them." - Genesis 3:21 KJV
God showed the human race substitution. An animal's blood was shed for them so they could be warm and survive their new environment. God didn't sell them anything. The serpent was selling something to Eve apart from Adam and God. God gave them both something.
"And so it is written, The first man Adam was made a living soul; the last Adam was made a quickening spirit. Howbeit that was not first which is spiritual, but that which is natural; and afterward that which is spiritual. The first man is of the earth, earthy: the second man is the Lord from heaven. As is the earthy, such are they also that are earthy: and as is the heavenly, such are they also that are heavenly. And as we have borne the image of the earthy, we shall also bear the image of the heavenly." - 1 Corinthians 15:45-49 KJV
"But it shall not be so among you: but whosoever will be great among you, let him be your minister; And whosoever will be chief among you, let him be your servant: Even as the Son of man came not to be ministered unto, but to minister, and to give his life a ransom for many." - Matthew 20:26-28 KJV
The living soul joins and dies but the quickening spirit dies to self through identification without compromise and lives.
Jesus became the ultimate substitute. He walked the Earth as the lamb of God who takes away the sins of the world.
Soulish life looks prosperous until the road block comes. Spiritual life looks to the One who gave all. It dies, gets buried and is raised three short days later. Spiritual life sits in Heavenly places because the right substitute is already sitting there.
"Who, being in the form of God, thought it not robbery to be equal with God: But made himself of no reputation, and took upon him the form of a servant, and was made in the likeness of men: And being found in fashion as a man, he humbled himself, and became obedient unto death, even the death of the cross. Wherefore God also hath highly exalted him, and given him a name which is above every name: That at the name of Jesus every knee should bow, of things in heaven, and things in earth, and things under the earth; And that every tongue should confess that Jesus Christ is Lord, to the glory of God the Father." - Philippians 2:6-11 KJV
Grace is intertwined with this idea. God gave great grace when He gave His Son to us. Jesus had an attitude of grace that went hand in hand with the idea of giving His life.
"All this is from God, who through Christ reconciled us to himself and gave us the ministry of reconciliation; that is, in Christ God was reconciling the world to himself, not counting their trespasses against them, and entrusting to us the message of reconciliation." - 2 Corinthians 5:18-19 ESV
"And by that will we have been sanctified through the offering of the body of Jesus Christ once for all." - Hebrews 10:10 ESV
A once and for all sacrifice has been made by the once and for all substitute.
Have we as individuals learned the lesson or will we just bite the apple that is handed to us?