but by God alone is man made happy, if we speak of perfect Happiness.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic happiness God
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

“such as raising the dead to life, restoring sight to the blind, and such like. Now it has been shown above (A. 5) that Happiness is a good surpassing created nature. Therefore it is impossible that it be bestowed through the action of any creature: but by God alone is man made happy, if we speak of perfect Happiness. If, however, we speak of imperfect happiness, the same is to be said of it as of the virtue, in whose act it consists. Reply Obj. 1: It often happens in the case of active powers ordained to one another, that it belongs to the highest power to reach the last end, while the lower powers contribute to the attainment of that last end, by causing a disposition thereto:” source