Most people to day have some sort of mechanism that can tell them what time it is. Do you remember the song from the group Chicago, "Does anybody really know what time it is?" I believe it was one of their first songs to hit the charts. But the concept was that we are all so busy that we really don't know what time it is in our lives. We're all so busy doing "things" and "stuff" that what really is important in our lives goes by so fast and you can't push the undo button!
The concept of time exists because everything that has life dies so we measure that existence in increments of time. If none of us died, time would have no value. But we will all die eventually, physically speaking, but our spirits live forever. But our physical bodies don't last forever. What would you do if you were told you had only a month or couples of months left to live? What would be your priorities? How would you view the various things in your life?