According to Christian doctrine, original sin is a state of alienation from God. It is present at birth and collectively inherited from the first sin of the biblical Adam and Eve in the Garden of Eden (Genesis 2:4-3:24).
In the Genesis account, Adam and Eve eat the forbidden fruit growing on the tree of knowledge at the garden center.¹ Their eyes are opened, they become ashamed of their nakedness and cover themselves. So they hide from God who is “walking” in the garden. When God discovers them he basically flips out. God curses the serpent and tells the woman that he will make childbirth much more painful. Moreover, the serpent and human beings will forever be in violent conflict.
God then casts Adam and Eve out of the garden into the world beyond. The garden’s entrance is barred by a cherubim with a revolving, fiery sword. Adam and Eve’s offspring are cursed for generations. No longer is everything easy and good. They must not merely work, as they did in the garden, but rather, toil for their food (Genesis 3).
To the modern mind, this story seems to be rooted in primitive myth and beliefs. God is supremely anthropomorphic. The tale also seems sexist because Eve is blamed for the Fall. She is also condemned to be subservient to her husband, whom she desires all the same.
The Church Fathers mention the idea of original sin as early as the 2nd century. They believed, as do many subsequent Christians, that their views were justified by Biblical scripture. The practice of harkening back to Biblical scripture to try to legitimize the idea of original sin involves both the Old and New Testaments.
Christians generally say that the New Testament “fulfills” the Old Testament, so the NT has to sort of patch up and surpass a good deal of the gobbledygook, primitive hate and sexism found in the OT.²
In the New Testament, for example, the apostle Paul says sin came into the world because of one man—that is, Adam (Romans 5:12). For all his apparent visionary experience of the risen Christ, Paul still believes in the ancient OT story as if it were literal fact.³
The story of Adam and Eve is also mentioned in 1 Timothy 2 and upheld by many contemporary Christians who, perhaps inadvertently or unconsciously, legitimize sexism with scripture:
A woman must learn in quietness and full submissiveness. I do not permit a woman to teach or exercise authority over a man; she is to remain quiet. For Adam was formed first, and then Eve. And it was not Adam who was deceived, but the woman who was deceived and fell into transgression. Women, however, will be saved through childbearing, if they continue in faith, love, and holiness, with self-control (1 Timothy 2 [11-15])
For Catholics, there are two exceptional people in human history who do not inherit the taint of original sin: Jesus and his mother the Virgin Mary. Protestants and Anglicans generally do not accept that Mary was born without sin. And the Orthodox position has its own complications.
Recently, theologians like Rudolf Bultmann (1884-1976) have attempted to separate the mythic and cultural aspects of the Bible, on the one hand, from its spiritual essence, on the other hand. For Bultmann, the terms “authentic existence” and “inauthentic existence” are more meaningful to modern minds than are their traditional antecedents, “salvation” and “sin.” Other contemporary theologians challenge the notion of inheriting sin from a mythic past. And present-day thinkers like astronomer David Darling suggest that time is holistic instead of linear, which complicates the idea of original sin.
Surely there had to have been some special point of origin? But no. What was needed was a more panoramic view in which the universe, past, present, and future, was seen as having always been there–a permanent, all-encompassing, space-time eternity. Of course, it was natural for man, whose left-brain consciousness produced the illusion of “passing” time to think of past and future as somehow different in status. To dwell, moreover, on that elusive moment called now which transformed the potentiality of future events into the actuality of the past. But “now” was, in truth, only a chimera. Every point in space and time coexisted with equal importance. The future was there from the beginning as surely as was the past.4
If viewed this way, the idea of an evil force that runs through all-time and which compels humanity to sin might make more sense than stories primarily based on linear time.5
¹ Eve was tempted first by the serpent. After eating the fruit, she hands it to Adam, who also eats. The fruit is usually depicted as an apple, especially in Western culture. However, the actual fruit is unknown.
² Not to say that the NT is devoid of cultural bias. It may have done away with violence. But it still arguably discriminates on the basis of ethno-religion and sex in places.
³ Possibly many people today have genuine mystical experiences and yet unconsciously assume that this proves a particular set of theological stories and traditions. If a church gives them all the answers, they don’t have to bother reflect any further. And people like me who simply want to use the mind God gave them, are under the sway of “Satan.”
4 David Darling, Deep Time, New York: Delacorte Press, 1989, pp. 187-188).
The Catholic position is summed up here: http://www.catholic.com/tracts/adam-eve-and-evolution This Catholic position is at least partially rooted in a traditional understanding of linear time, and probably won’t be reconsidered by the Church until sufficient political pressure acts upon the Catholic hierarchy–that is, until the idea of holistic time becomes more commonplace. And that, ironically, will likely take centuries. Even the apparently “smart” Catholics, the Jesuits, are still largely rooted in traditional ways of looking at and analyzing problems. At least, they are compelled to uphold Catholic teachings during the Mass. The suppression of free thinking among the clergy and the faithful runs deep into Catholic history. Not as obvious now, as say, the house arrest of Galileo, it seems the Vatican still keeps a pretty firm grip on its shepherds; even if, perhaps, losing its grip on many of its sheep. However, Catholic conservatism isn’t entirely bad because it defends the Church against nutty extremists. But it can also hinder true theological progress and fair theological practice.
5 Many Christians and Catholics say that Jesus exists in or simply is “all-time,” so the Catholic view is not so linear. But the Bible tells us that Satan fell some time after the initial creation (see http://www.gotquestions.org/Satan-fall.html). Wikipedia lists some parallel stories to the Garden of Eden. Not exactly the same but with similarities: https://en.wikipedia.org/wiki/Garden_of_Eden#Parallel_concepts