If we are angry with those who harm others, and seek to be avenged on them, it is because those who are injured belong in some way to us
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic harm injuring
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

“First, in so far as he despises God in His commandments. Secondly, in so far as he harms himself or another; which injury redounds to God, inasmuch as the person injured is an object of God's providence and protection. Reply Obj. 2: If we are angry with those who harm others, and seek to be avenged on them, it is because those who are injured belong in some way to us: either by some kinship or friendship, or at least because of the nature we have in common. Reply Obj. 3: When we take a very great interest in a thing, we look upon it as our own good; so that if anyone despise it, it seems as though we ourselves were despised and injured.” source