For what is by essence in anything, is in it essentially. But God is not essentially in things; for He does not belong to the essence of anything. Therefore it ought not to be said that God is in things by essence, presence and power.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic power God
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/17611/pg17611-images.html

Context

“THIRD ARTICLE [I, Q. 8, Art. 3]
Whether God Is Everywhere by Essence, Presence and Power?
Objection 1: It seems that the mode of God's existence in all things is not properly described by way of essence, presence and power. For what is by essence in anything, is in it essentially. But God is not essentially in things; for He does not belong to the essence of anything. Therefore it ought not to be said that God is in things by essence, presence and power. Obj. 2: Further, to be present in anything means not to be absent from it. Now this is the meaning of God being in things by His essence, that He is not absent from anything. Therefore the presence of God in all things by essence and presence means the same thing.” source