Reply Obj. 1: Incorporeal things are in place not by contact of dimensive quantity, as bodies are but by contact of power.
Reply Obj. 2: The indivisible is twofold. One is the term of the continuous; as a point in permanent things, and as a moment in succession; and this kind of the indivisible in permanent things, forasmuch as it has a determinate site, cannot be in many parts of place, or in many places; likewise the indivisible of action or movement, forasmuch as it has a determinate order in movement or action, cannot be in many parts of time. Another kind of the indivisible is outside of the whole genus of the continuous; and in this way incorporeal substances, like God, angel and soul, are called indivisible. Such a kind of indivisible does not belong to the continuous, as a part of it, but as touching it by its power; hence, according as its power can extend itself to one or to many, to a small thing, or to a great one, in this way it is in one or in many places, and in a small or large place.
Reply Obj. 3: A whole is so called with reference to its parts. Now part is twofold: viz. a part of the essence, as the form and the matter are called parts of the composite, while genus and difference are called parts of species. There is also part of quantity into which any quantity is divided. What therefore is whole in any place by totality of quantity, cannot be outside of that place, because the quantity of anything placed is commensurate to the quantity of the place; and hence there is no totality of quantity without totality of place. But totality of essence is not commensurate to the totality of place. Hence it is not necessary for that which is whole by totality of essence in a thing, not to be at all outside of it. This appears also in accidental forms which have accidental quantity; as an example, whiteness is whole in each part of the surface if we speak of its totality of essence; because according to the perfect idea of its species it is found to exist in every part of the surface. But if its totality be considered according to quantity which it has accidentally, then it is not whole in every part of the surface. On the other hand, incorporeal substances have no totality either of themselves or accidentally, except in reference to the perfect idea of their essence. Hence, as the soul is whole in every part of the body, so is God whole in all things and in each one. _______________________
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. Therefore it is superfluous to say that God is present in things by His essence, presence and power.
Obj. 3: Further, as God by His power is the principle of all things, so He is the same likewise by His knowledge and will. But it is not said that He is in things by knowledge and will. Therefore neither is He present by His power.
Obj. 4: Further, as grace is a perfection added to the substance of a thing, so many other perfections are likewise added. Therefore if God is said to be in certain persons in a special way by grace, it seems that according to every perfection there ought to be a special mode of God's existence in things.
On the contrary, A gloss on the Canticle of Canticles (5) says that, "God by a common mode is in all things by His presence, power and substance; still He is said to be present more familiarly in some by grace." [*The quotation is from St. Gregory, (Hom. viii in Ezech.)].