But love does not cause union of essence; else love could not be between things essentially distinct. On the other hand, love does not cause union of likeness, but rather is caused by it, as stated above (Q. 27, A. 3). Therefore union is not an effect of love.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic likeness union
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

“2: Further, every union is either according to essence, thus form is united to matter, accident to subject, and a part to the whole, or to another part in order to make up the whole: or according to likeness, in genus, species, or accident. But love does not cause union of essence; else love could not be between things essentially distinct. On the other hand, love does not cause union of likeness, but rather is caused by it, as stated above (Q. 27, A. 3). Therefore union is not an effect of love. Obj. 3: Further, the sense in act is the sensible in act, and the intellect in act is the thing actually understood. But the lover in act is not the beloved in act. Therefore union is the effect of knowledge rather than of love.
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