Life is short, stop sending time as if you have an unlimited supply, at the same time don't fear death as if it were evil.

Readings: Plato's Apology http://classics.mit.edu/Plato/apology.html
On the Shortness of Life: https://archive.org/stream/SenecaOnTheShortnessOfLife/Seneca+on+the+Shortness+of+Life_djvu.txt
The Meditations of Marcus Aurelius : http://classics.mit.edu/Antoninus/meditations.html