since a man's love for a thing is proved to be so much the greater, according as that which he despises for its sake is more dear to him, or that which he chooses to suffer for its sake is more odious.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic suffering love
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

“A virtuous act may be considered in another way, in comparison with its first motive cause, which is the love of charity, and it is in this respect that an act comes to belong to the perfection of life, since, as the Apostle says (Col. 3:14) , that "charity . . . is the bond of perfection." Now, of all virtuous acts martyrdom is the greatest proof of the perfection of charity: since a man's love for a thing is proved to be so much the greater, according as that which he despises for its sake is more dear to him, or that which he chooses to suffer for its sake is more odious. But it is evident that of all the goods of the present life man loves life itself most, and on the other hand he hates death more than anything, especially when it is accompanied by the pains of bodily torment, "from fear of which even dumb animals refrain from the greatest pleasures,"” source