When you live in the past, what you are trying to do is change something that’s unchangeable and the time spent doing this is wasted by living in a delusion of what isn’t instead of a reality of what is.
Subtle is the foe of the person who doesn’t know their own mind for they know not what they do. It’s imperative to know your own mind if you ever want to be free of its grasp, and don’t think for a minute that you’re not in its grasp, why else would you want something to be different that couldn’t be change. Every moment spent in the past is time wasted on trying to change the unchangeable. You wouldn’t purposely waste time living in a place where life has already occurred, would you? So if you wouldn’t purposely do this, why does it occur?
All of life is precious, so it’s not that any moment of life is truly wasted, but the more time that’s spent trying to change the unchangeable, the less time one lives in the reality of what is. And it’s only in the way one’s own mind has been developed that makes one think that the unchangeable can be changed. Look and see this for yourself, for subtle is the foe of the person who doesn’t know their own mind for they know not what they do.
You have the capability to be mindful of every moment of everyday, but this will take much discipline. Either you will control your mind or you will be controlled by it, but understand, when you’re controlled by it, you know not what you do. So take heed for the mind is a subtle foe, and if you don’t learn to stop trying to change the unchangeable, the moments spent doing this will just continue to make you live a life not to the fullest because it’s being wasted living in moments that aren’t real.