But to render to a man what belongs to him, as justice requires, is of necessity. Therefore it is not meritorious. Yet it is by virtuous actions that we gain merit. Therefore justice is not a virtue.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic justice action
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

“Therefore to do what one ought to do, is not a virtuous deed. And yet it is an act of justice. Therefore justice is not a virtue.
Obj. 2: Further, that which is done of necessity, is not meritorious. But to render to a man what belongs to him, as justice requires, is of necessity. Therefore it is not meritorious. Yet it is by virtuous actions that we gain merit. Therefore justice is not a virtue. Obj. 3: Further, every moral virtue is about matters of action. Now those things which are wrought externally are not things concerning behavior but concerning handicraft, according to the Philosopher (Metaph. ix) [*Didot ed., viii, 8] .” source