Patience is said to have "a perfect work," by enduring evils, wherein it excludes not only unjust revenge, which is also excluded by justice; not only hatred, which is also suppressed by charity; nor only anger, which is calmed by gentleness
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic calm anger
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

“Hence justice is simply greater than liberality, as being more universal, and as being its foundation: while liberality is greater relatively since it is an ornament and an addition to justice. Reply Obj. 2: Patience is said to have "a perfect work," by enduring evils, wherein it excludes not only unjust revenge, which is also excluded by justice; not only hatred, which is also suppressed by charity; nor only anger, which is calmed by gentleness; but also inordinate sorrow, which is the root of all the above. Wherefore it is more perfect and excellent through plucking up the root in this matter. It is not, however, more perfect than all the other virtues simply.” source