"I was obliged to be industrious; whoever is equally industrious will succeed equally well."

Hat tip Elaine Butler.

"Ich habe fleißig seyn müssen; wer eben so fleißig ist, der wird es eben so weit bringen können."

     Johann Sebastian Bach (1685-1750), as channeled by Johann Nikolaus Forkel (1749-1818), Ueber Johann Sebastian Bachs Leben, Kunst und Kunstwerke. Für patriotische Verehrer echter musikalischer Kunst (Leipzig:  Hoffmeister und Kuehnel, 1802), 45 (chap. 8).  Another translation:

"I was made to work; if you are equally industrious you will be equally successful."

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"I had to be industrious. . . ."