From another thread:
Dying before death is allowing that which has arisen to cease. This teaching is about the mind; we’ll let the body die when it’s time for it to die. If it lives another minute, or another fifty years, or another eighty years, or whatever – that’s up to the body. We’re in no hurry to die, nor are we trying to live longer than necessary. We allow this body to live its lifespan, because it’s not self; it does not belong to us. However long this body breathes and lives is all right. It’s not mine anyway. But during the time that it’s alive, there’s an opportunity to die before death: to die to ignorance and selfishness; to die to greed, hatred, and delusion; to let all these things die; to let them go and let them cease. So one is observing death as it’s really happening, as the ending, the cessation of these things we tend to regard as ourselves, but are merely mortal conditions.
This important and realistic approach is expressed in the Sufi saying, 'Die before you die'. The same understanding is expressed in the above quote. I would suggest that as we stop grasping at our life, nirvana, practice, study etc, something happens. What does it take to die in this spiritual sense? The truth is very simple, when you are ready, 'you' will start to die. However do most of us still have living to attend to? Are we ready yet?