"You're a shadow, you slip out of your own skin, like molting, shedding your own history and your own future, leaving behind everything you ever were or wanted or believed". Why is this quote important?

This quote illustrates what true terror feels like.... knowing that you can die at any moment and feeling as if you're watching your own death because there's nothing you can do but wait. O'Brien uses this quote to illustrate the reality..... the shared terror you cannot understand unless you've been face to face with it.