For when sorrow is inflicted upon someone, there arises within him a desire of the sensitive appetite to repel this injury brought upon himself or others. Hence anger is a passion composed of sorrow and the desire of revenge.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic anger revenge
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/19950/pg19950-images.html

Context

“58:10, "the zeal of Thy house hath eaten me up," were fulfilled in Him.
I answer that, As was said in the Second Part (I-II, Q. 46, A. 3, ad 3, and II-II, Q. 158, A. 2, ad 3) , anger is an effect of sorrow. For when sorrow is inflicted upon someone, there arises within him a desire of the sensitive appetite to repel this injury brought upon himself or others. Hence anger is a passion composed of sorrow and the desire of revenge. Now it was said (A. 6) that sorrow could be in Christ. As to the desire of revenge it is sometimes with sin, i.e. when anyone seeks revenge beyond the order of reason: and in this way anger could not be in Christ, for this kind of anger is sinful.” source