But heard are the voices,
Heard are the sages,
The Worlds and the Ages:
“Choose well: your choice is
Brief, and yet endless.”[Doch rufen von drüben
Die Stimmen der Geister
Die Stimmen der Meister:
Bersäumt nich zu üben
Die Kräfte des Guten.]Johann Wolfgang von Goethe (1749-1832) German poet, statesman, scientist
“Symbolum” (1815) [tr. Carlyle (1843)]
(Source)
(Source (German)).
Carlyle's loose translation first appears in Past and Present, Book 2, ch. 17 "The Beginnings" (1843), then is expanded in a speech at the University of Edinburgh (2 Apr 1866), reprinted (with Goethe's original) in On the Choice of Books (1877).
"Choose well: your choice is brief and yet endless," is sometimes attributed to Ella Winter. She references it in an anecdote in And Not to Yield: An Autobiography (1963).