First off: The Garden was not described as "perfect" like heaven would be perfect, but as being very good, which can mean as good as could be at the time for the purpose needed. There is no tree of knowledge, satan and fleshly beings in heaven.The doctrine of original sin and the understanding of the fall from grace and the ensuing change that affected the whole world are not the same. Original sin states we are guilty of Adam’s sin, which we are not. The fall, however, because of its universal consequences affects everyone in that sin entered the world, creating a fallen state (as compared to the perfect state in the Garden of Eden).
All of creation changed, including our nature, putting us in rebellion to God. If we, ourselves, our nature, didn’t change there wouldn’t have been a need to cast us out of the Garden and develop a plan of salvation. It is all entwined together.
God's grace is all around us, in contrast to sin which is also around us on earth, but God determines what sin is and conveys that to us with the Law written on our hearts. Selfishness, lust and coveting was around Adam and Eve in the Garden, but these were not sins prior to them having the knowledge of good and evil which would be knowledge of selfishness, lust and coveting. God did not make these sins, to be "sins", prior to eating the fruit and gaining the knowledge that they were sins.
A baby is not in rebellion to God.
The Garden story tell us many things including the fact that the Garden was a lousy (impossible) place for humans to fulfill their earthly objective.
This messed up world with lots of tragedies, satan, roaming around, death, hell, and Christ having to go to the cross is actually the very best place for willing humans to fulfill their earthly objective.
Upvote
0