Therefore God ought to be loved chiefly and before all out of charity: for He is loved as the cause of happiness, whereas our neighbor is loved as receiving together with us a share of happiness from Him.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic happiness sharing
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

“I answer that, Each kind of friendship regards chiefly the subject in which we chiefly find the good on the fellowship of which that friendship is based: thus civil friendship regards chiefly the ruler of the state, on whom the entire common good of the state depends; hence to him before all, the citizens owe fidelity and obedience. Now the friendship of charity is based on the fellowship of happiness, which consists essentially in God, as the First Principle, whence it flows to all who are capable of happiness.
Therefore God ought to be loved chiefly and before all out of charity: for He is loved as the cause of happiness, whereas our neighbor is loved as receiving together with us a share of happiness from Him. Reply Obj. 1: A thing is a cause of love in two ways: first, as being the reason for loving. In this way good is the cause of love, since each thing is loved according to its measure of goodness. Secondly, a thing causes love, as being a way to acquire love.” source