Do they believe in original sin?
Mormons do not believe in original sin, in the sense that the human race bears any responsibility or guilt for the actions of Adam and Eve. In fact, Mormons believe that their transgression made possible the coming of the human race into the world, with the consequent opportunities to grow through the full range of mortal experience. It was, in that sense, a “fortunate fall,” and Eve especially a heroine rather than villain in the human story. At the same time, Mormons recognize that it is not possible to live a life free of sin.
