I talked about living the moment before. By living the moment, I mean being content and doing your best to serve God. If you don't live the moment, then it's lost and gone forever. If you dwell upon your past, you are not living the moment. If you are not content now and hope that the future will be better, you are not living the moment. The present moment is the only moment you have. To dwell upon the past and/or future is to not live at all.