No longer put your hopes in things that fall away, but let your mind seize the joys of light eternal.
(Latin: Amplius in rebus noli sperare caducis, sed capiat tua mens aeternae gaudia lucis.)
The source for the proverb is Philosophia Patrum by Julius Wegeler (GoogleBooks). The poster is made with AutoMotivator. The image is from Cheezburger.