But moral evil is lessened by passion: for he sins less, who sins from passion, than he who sins deliberately.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic passion 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

“(De Civ. Dei ix, 5) . Therefore it is better to do such like deeds without than with a passion of the soul. Obj. 3: Further, just as moral evil depends on its relation to reason, so also does moral good. But moral evil is lessened by passion: for he sins less, who sins from passion, than he who sins deliberately. Therefore he does a better deed, who does well without passion, than he who does with passion. On the contrary, Augustine says (De Civ. Dei ix, 5) that "the passion of pity is obedient to reason, when pity is bestowed without violating right, as when the poor are relieved, or the penitent forgiven."” source