[Stormcrow]

To clarify: when I said "there was no original sin leading to mortality in Tolkien," I was being specific. The "leading to mortality" is an important part of that. Men didn't start out immortal and gain mortality through original sin.

Whether original sin exists at all in Tolkien can be debated. Yes, Men have a darkness in their past, but this darkness can be overcome: the early Numenoreans, for example, have done so. It takes Sauron and a whole new cycle of temptation to corrupt them. Lifespan is certainly influenced by corruption, but nothing Morgoth or Sauron do can change the essential morality or immortality of the Children of Iluvatar.