Therefore it is more meritorious to love one's friend than to love one's enemy.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic love enemies
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/18755/pg18755-images.html

Context

“On the contrary, The better an action is, the more meritorious it is. Now it is better to love one's friend, since it is better to love a better man, and the friend who loves you is better than the enemy who hates you. Therefore it is more meritorious to love one's friend than to love one's enemy. I answer that, God is the reason for our loving our neighbor out of charity, as stated above (Q. 25, A. 1) . When therefore it is asked which is better or more meritorious, to love one's friend or one's enemy, these two loves may be compared in two ways, first, on the part of our neighbor whom we love, secondly, on the part of the reason for which we love him.” source