for a father naturally loves his son more than a brother loves his brother; although the son does not love his father as much as he is loved by him.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic love father
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/17611/pg17611-images.html

Context

“the result of which is that some are placed in subjection to others as a penalty. Reply Obj. 2: Equality is the cause of equality in mutual love. Yet between those who are unequal there can be a greater love than between equals; although there be not an equal response: for a father naturally loves his son more than a brother loves his brother; although the son does not love his father as much as he is loved by him. Reply Obj. 3: The cause of inequality could be on the part of God; not indeed that He would punish some and reward others, but that He would exalt some above others; so that the beauty of order would the more shine forth among men.” source