But it is a man's duty to be good to those who have been good to him.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic duty good
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
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Context

“Therefore in doing acts of kindness we are not bound to give the preference to those who are most closely united to us. Obj. 3: Further, we should pay what is due before conferring gratuitous favors. But it is a man's duty to be good to those who have been good to him. Therefore we ought to do good to our benefactors rather than to those who are closely united to us. Obj. 4: Further, a man ought to love his parents more than his children, as stated above (Q. 26, A.” source