He who acts unjustly acts unjustly to himself, because he makes himself bad.
 Marcus Aurelius, Meditations (c. 170 - 180). copy citation

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Author Marcus Aurelius
Source Meditations
Topic acts
Date c. 170 - 180
Language English
Reference
Note Translated by George Long
Weblink https://www.gutenberg.org/files/15877/15877-h/15877-h.htm

Context

“But now thou seest how great is the trouble arising from the discordance of those who live together, so that thou mayst say, Come quick, O death, lest perchance I, too, should forget myself. [A] Note 1 of the Philosophy, p. 76. 4. He who does wrong does wrong against himself. He who acts unjustly acts unjustly to himself, because he makes himself bad. 5. He often acts unjustly who does not do a certain thing; not only he who does a certain thing. 6. Thy present opinion founded on understanding, and thy present conduct directed to social good, and thy present disposition of contentment with everything which happens+—that is enough.” source