When a man does what he ought, he brings no gain to the person to whom he does what he ought, but only abstains from doing him a harm.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic gain harm
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/18755/pg18755-images.html

Context

“Hence, since justice regulates human operations, it is evident that it renders man's operations good, and, as Tully declares (De Officiis i, 7) , good men are so called chiefly from their justice, wherefore, as he says again (De Officiis i, 7) "the luster of virtue appears above all in justice." Reply Obj. 1: When a man does what he ought, he brings no gain to the person to whom he does what he ought, but only abstains from doing him a harm. He does however profit himself, in so far as he does what he ought, spontaneously and readily, and this is to act virtuously. Hence it is written (Wis. 8:7) that Divine wisdom "teacheth temperance, and prudence, and justice, and fortitude, which are such things as men” source