There is a meditation in some branches of Buddhism that involves (among other things - posture, breathing etc.) envisioning oneself as a stone statue in a desert; then seeing that statue slowly worn away by the blowing sand, slowly removing major features, then continuing on to wear away the minor features, and then slowly eroding the head and torso, legs - until all that is left is the smooth wind-blown sand.
Sounds gruesome but in fact it is refreshing.
In any case - this from one of my fav Saints:
Gregory of Nazianzus, Orations 7.19.1 (Funeral Oration on his Brother Caesarius; tr. Leo P. McCauley):
Such, brethren, is our life, we whose existence is so transitory. Such is the game we play upon earth: we do not exist and we are born, and being born we are dissolved. We are a fleeting dream, an apparition without substance, the flight of a bird that passes, a ship that leaves no trace upon the sea. We are dust, a vapor, the morning dew, a flower growing but a moment and withering in a moment.