that reflects the jewish concept that sin was introduced to mankind by the original sin of Adam and Eve and that's who evil came into the world
Well, that's true. I was focusing too much on the curses pronounced on Adam and Eve, but the fact remains that they ate of the tree of knowledge of good and evil and it "opened their eyes". Apparently that means that we inherited the potential for evil thoughts from our first parents. So I stand corrected on that point.
My intention was to make the point that it was only post-Paul that Christians began to say that man was created perfect. This was because the idea of God had advanced from (a) a powerful man who created life from clay, or a tribal war god (in the oldest Jewish stories) to (b) the most powerful tribal god (later Jewish writings), to (c) a unique, omnipotent, omniscient being (Christianity, modern Judaism?). So Christians could no longer conceive that this kind of God would ever create something flawed.
Thus they changed the Jewish concept of inheriting death and "sin" (the potential for evil thoughts) into the inheriting of "imperfection" (a general failure of the body and mind to function as God originally intended). They ignored the significance of the tree of life in the Eden story (viz, that we were not created to live forever, but required the tree to sustain eternal life) and they ignored the fact that God only pronounced specific curses on man and woman.
Now that we know about DNA, this leads to an incredible deviation from the original Jewish thought, because a science-minded Christian is left to try to ponder how imperfection actually works on the genetic level. How did Adam's sin cause his DNA to become flawed? Which workings of our body are flawed and which still function as intended? Were we supposed to have body odor, to get gassy from time to time? Were women really designed to bleed every month? And why did God design Adam and Eve with a genetic booby-trap triggered by disobedience? Et cetera.
Paul would be totally baffled by this whole way of looking at things. When he said that Jesus was needed to redeem us from Adam's sin, he didn't mean that Jesus was perfect like Adam -- he meant that Jesus was another son of God in human form. That's why there's a genealogy tracing Jesus back to Adam, "son of God". God was the father of two humans, Adam and the incarnated Jesus. That's why Jesus could be the redeemer, according to Paul -- not because God somehow prevented the baby Jesus from inheriting genetic imperfection from his mother.