Being is consequent upon nature, not as upon that which has being, but as upon that whereby a thing is
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/19950/pg19950-images.html

Context

“, and not accidentally, it follows that by the human nature there accrued to Him no new personal being, but only a new relation of the pre-existing personal being to the human nature, in such a way that the Person is said to subsist not merely in the Divine, but also in the human nature. Reply Obj. 1: Being is consequent upon nature, not as upon that which has being, but as upon that whereby a thing is: whereas it is consequent upon person or hypostasis, as upon that which has being. Hence it has unity from the unity of hypostasis, rather than duality from the duality of the nature. Reply Obj. 2: The eternal being of the Son of God, which is the Divine Nature, becomes the being of man, inasmuch as the human nature is assumed by the Son of God to unity of Person.” source