Work, as we usually think of it, is energy expended for a further end in view; play is energy expended for its own sake, as with children's play, or as manifestation of the end or goal of work, as in "playing" chess or the piano. Play in this sense, then, is the fulfillment of work, the exhibition of what the work has been done for.
(Northrop Frye (1912-1991), Canadian critic. The Great Code: The Bible in Literature, ch. 5, Harcourt Brace (1983).)
Do not put off your work until tomorrow and the day after. For the sluggish worker does not fill his barn, nor the one who puts off his work; industry aids work, but the man who puts off work always wrestles with disaster.
(Hesiod (c. 8th century B.C.), Greek didactic poet. Works and Days, 410.)