The second thing to know is that my time's are in God's hands. James is very realistic when he says, “You do not know about tomorrow. What is your life? For you are a mist that appears for a little time and then vanishes. Instead you ought to say, 'If the Lord wills, we shall live and we shall do this or that” (James 4:14-14). Only God knows when I'm going to get the final curtain call and so far He isn't telling. That's probably a blessing; at least it's not something I should be worrying about.
Third, our life span is “threescore years and ten, or even by reason of strength fourscore;” (Psalm 90:10) that is 70 or 80 years, at least at the time when the Psalmist was writing. Now I'm already in my seniority and time's a wasting! One of the things that many of us in our seniority notice is the illusion that the older you get, the faster time seems to move. “Oh no! It's almost Advent again,” but that only a matter of perspective. If you view time from Eternity it flashes by faster that the flash of a firecracker. One of the great miracles was that the King of Forever humbled Himself to enter into the millisecond of time.
Having said all that, time is precious and needs to be spent wisely and in acknowledgement that there is “a time for every matter under heaven: a time to be born, and a time to die; a time to plant, and a time to pluck up what is planted: a time to kill, and a time to heal; a time to break down, and a time to build up; a time to weep, and a time to laugh; a time to mourn, and a time to dance; a time to cast away stones, and a time to gather stones together; a time to embrace, and a time to refrain from embracing (that one will get you in trouble with an airline if you fail to recognize it); a time to seek, and a time to lose; a time to keep, and a time to cast away, a time to keep silence, and a time to speak; a time to love, and a time to hate, a time for war, and a time for peace (Ecc. 3:1-8).
There is a time for everything from working to relaxation, but I suspect that there isn't much time for just mindlessly staring at a wall. How do you spend your time? Time is always spent, deliberately or carelessly, it doesn't just drift away like sand in an hourglass; even not deciding how we spend time is a decision. When you think about time always remember that “He has made everything beautiful in its time; also he has put eternity into man's mind” (Ecc. 4:11).