Ephesians 5:16 redeeming the time, because the days are evil.
One thing we have only got one shot at on earth is time. So far nobody has been able to invent a time machine where they will be able to go back and relive a certain time.
This is why we are warned that we have to be wise with our time and not to waste it. I felt a bit guilty about using so much time to study in the past, but now I see how valuable it is, I have no worries about spending time with God in His Word!
Time spent listening to God is time well spent. Time spent running after the world is time wasted when we look to the reward we have in heaven.