Therefore a human action does not deserve blame, by reason of its being evil or sinful; and, consequently, neither does it deserve praise, by reason of its being good.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic action evil
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/17897/pg17897-images.html

Context

“Objection 1: It would seem that a human action does not deserve praise or blame by reason of its being good or evil. For "sin happens even in things done by nature" (Phys. ii, 8) . And yet natural things are not deserving of praise or blame (Ethic. iii, 5) . Therefore a human action does not deserve blame, by reason of its being evil or sinful; and, consequently, neither does it deserve praise, by reason of its being good. Obj. 2: Further, just as sin occurs in moral actions, so does it happen in the productions of art: because as stated in Phys. ii, 8 "it is a sin in a grammarian to write badly, and in a doctor to give the wrong medicine." But the artist is not blamed for making something bad: because the artist's work is such, that he can produce a good or a bad thing, just as he lists.” source