In the midst of hopes and ...

In the midst of hopes and cares, of apprehensions and of disquietude, regard every day that dawns upon you as if it was to be your last; then super-added hours, to the enjoyment of which you had not looked forward, will prove an acceptable boon.
In the midst of hopes and cares, of apprehensions and of disquietude, regard every day that dawns upon you as if it was to be your last; then super-added hours, to the enjoyment of which you had not looked forward, will prove an acceptable boon.

Quotes from the same author

Adversity has the effect of eliciting talents, which in prosperous circumstances would have lain dormant.
A heart well prepared for adversity in bad times hopes, and in good times fears for a change in fortune.
Begin, be bold, and venture to be wise.
Men more quickly and more gladly recall what they deride than what they approve and esteem.
Help a man against his will and you do the same as murder him.