The Idea of Original Sin is believed by Christians to have come about thousands of years ago in the Garden of Eden located in Mesopotamia( modern-day Iraq) by, we are told, a woman that had a conversation with a "serpent".
God by all accounts had warned her husband to- be, Adam not to eat from the all knowing tree of good and evil or he would die the same day. But it turns out that Eve after a conversation with a serpent took its advice and decided to have a good ole' chomp of its fruit regardless. It has to be noted though, that Eve was never given this warning against the tree; he had warned only the Adam and at a time before Eve was even created. But this didn't stop the Church placing all the blame for original sin on the woman; Eve, and as a result all those "born of woman" are sinful, i.e. we have all inherited sin; Eve was now a temptress and seducer in the eyes of the Church and all done no doubt to establish male superiority over the woman and the so the women is informed that for encouraging the Adam and casting her influences upon him against god will , " your husband will rule over you".
At this point it is only the Adam that is exiled "Therefore the Lord God sent him forth from the garden of Eden". And it is not until later in the story we discover that Eve followed him. And they dwelt in the land of Elda.
We then hear of a secondary problem for the gods. It was another tree, the Tree of Life and it appears that this problematic tree was also the cause of the Adams expulsion "lest he put forth his hand and eat and live forever and be like us" although he hadn't touched this tree he was deprived of any of its benefit regardless.
It is difficult to understand the context of this whole saga, where the serpent has come from. Because god had created all the animals before he created the Adam yet not a single word about the creation of a serpent with the power to oppose him. Buy all accounts god had looked over his creation and "saw that it was good". But without any explanation a serpent with the human voice appears a totally independent creature over which god has no control!?
As I have wrote about in another thread - https://www.debateart.com/forum/topics/9943-the-myth-of-satan?page=1&post_number=1 - the Church dogma on the serpent /satan anomaly but doesn't appear anywhere in Genesis.
It wasn't until the church Father, St Augustine of Hippo of North Africa had pronounced in the 4th century that because Eve had enchanted and enticed her husband to eat from the forbidden tree that he pronounced the doctrine of "Original Sin" which insists to this very day. It maintains that owning to the transgression of Eve "mother of all living" all people are born is sin simply by virtue of having mothers!.
Of course, as per usual, it must have slipped the minds of the early Church Bishops that this would have included, Jesus.