Summa Theologica, Part I (Prima Pars) From the Complete...

Objection 1: It seems that power is not in God. For as primary matter is to power, so God, who is the first agent, is to act. But primary matter, considered in itself, is devoid of all act. Therefore, the first agent—namely, God—is devoid of power.

Obj. 2: Further, according to the Philosopher (Metaph. vi, 19), better than every power is its act. For form is better than matter; and action than active power, since it is its end. But nothing is better than what is in God; because whatsoever is in God, is God, as was shown above (Q. 3, A. 3). Therefore, there is no power in God.

Obj. 4: Further, it was shown above (Q. 14, A. 8; Q. 19, A. 4) that God's knowledge and will are the cause of things. But the cause and principle of a thing are identical. We ought not, therefore, to assign power to God; but only knowledge and will.

I answer that, Power is twofold—namely, passive, which exists not at all in God; and active, which we must assign to Him in the highest degree. For it is manifest that everything, according as it is in act and is perfect, is the active principle of something: whereas everything is passive according as it is deficient and imperfect. Now it was shown above (Q. 3, A. 2; Q. 4, AA. 1, 2), that God is pure act, simply and in all ways perfect, nor in Him does any imperfection find place. Whence it most fittingly belongs to Him to be an active principle, and in no way whatsoever to be passive. On the other hand, the notion of active principle is consistent with active power. For active power is the principle of acting upon something else; whereas passive power is the principle of being acted upon by something else, as the Philosopher says (Metaph. v, 17). It remains, therefore, that in God there is active power in the highest degree.

Reply Obj. 1: Active power is not contrary to act, but is founded upon it, for everything acts according as it is actual: but passive power is contrary to act; for a thing is passive according as it is potential. Whence this potentiality is not in God, but only active power.

Reply Obj. 2: Whenever act is distinct from power, act must be nobler than power. But God's action is not distinct from His power, for both are His divine essence; neither is His existence distinct from His essence. Hence it does not follow that there should be anything in God nobler than His power.

Reply Obj. 3: In creatures, power is the principle not only of action, but likewise of effect. Thus in God the idea of power is retained, inasmuch as it is the principle of an effect; not, however, as it is a principle of action, for this is the divine essence itself; except, perchance, after our manner of understanding, inasmuch as the divine essence, which pre-contains in itself all perfection that exists in created things, can be understood either under the notion of action, or under that of power; as also it is understood under the notion of suppositum possessing nature, and under that of nature. Accordingly the notion of power is retained in God in so far as it is the principle of an effect.

Reply Obj. 4: Power is predicated of God not as something really distinct from His knowledge and will, but as differing from them logically; inasmuch as power implies a notion of a principle putting into execution what the will commands, and what knowledge directs, which three things in God are identified. Or we may say, that the knowledge or will of God, according as it is the effective principle, has the notion of power contained in it. Hence the consideration of the knowledge and will of God precedes the consideration of His power, as the cause precedes the operation and effect. _______________________

Obj. 3: Further, the Philosopher proves (Phys. viii, 79) that if the power of any corporeal thing were infinite, it would cause instantaneous movement. God, however, does not cause instantaneous movement, but moves the spiritual creature in time, and the corporeal creature in place and time, as Augustine says (Gen. ad lit. 20, 22, 23). Therefore, His power is not infinite.

I answer that, As stated above (A. 1), active power exists in God according to the measure in which He is actual. Now His existence is infinite, inasmuch as it is not limited by anything that receives it, as is clear from what has been said, when we discussed the infinity of the divine essence (Q. 7, A. 1). Wherefore, it is necessary that the active power in God should be infinite. For in every agent is it found that the more perfectly an agent has the form by which it acts the greater its power to act. For instance, the hotter a thing is, the greater the power has it to give heat; and it would have infinite power to give heat, were its own heat infinite. Whence, since the divine essence, through which God acts, is infinite, as was shown above (Q. 7, A. 1) it follows that His power likewise is infinite.

Reply Obj. 1: The Philosopher is here speaking of an infinity in regard to matter not limited by any form; and such infinity belongs to quantity. But the divine essence is otherwise, as was shown above (Q. 7, A. 1); and consequently so also His power. It does not follow, therefore, that it is imperfect.

Reply Obj. 2: The power of a univocal agent is wholly manifested in its effect. The generative power of man, for example, is not able to do more than beget man. But the power of a non-univocal agent does not wholly manifest itself in the production of its effect: as, for example, the power of the sun does not wholly manifest itself in the production of an animal generated from putrefaction. Now it is clear that God is not a univocal agent. For nothing agrees with Him either in species or in genus, as was shown above (Q. 3, A. 5; Q. 4, A. 3). Whence it follows that His effect is always less than His power. It is not necessary, therefore, that the infinite power of God should be manifested so as to produce an infinite effect. Yet even if it were to produce no effect, the power of God would not be ineffectual; because a thing is ineffectual which is ordained towards an end to which it does not attain. But the power of God is not ordered toward its effect as towards an end; rather, it is the end of the effect produced by it.

Reply Obj. 3: The Philosopher (Phys. viii, 79) proves that if a body had infinite power, it would cause a non-temporal movement. And he shows that the power of the mover of heaven is infinite, because it can move in an infinite time. It remains, therefore, according to his reckoning, that the infinite power of a body, if such existed, would move without time; not, however, the power of an incorporeal mover. The reason of this is that one body moving another is a univocal agent; wherefore it follows that the whole power of the agent is made known in its motion. Since then the greater the power of a moving body, the more quickly does it move; the necessary conclusion is that if its power were infinite, it would move beyond comparison faster, and this is to move without time. An incorporeal mover, however, is not a univocal agent; whence it is not necessary that the whole of its power should be manifested in motion, so as to move without time; and especially since it moves in accordance with the disposition of its will. _______________________

Obj. 3: Further, it is said of God that He manifests His omnipotence "especially by sparing and having mercy" [*Collect, 10th Sunday after Pentecost]. Therefore the greatest act possible to the divine power is to spare and have mercy. There are things much greater, however, than sparing and having mercy; for example, to create another world, and the like. Therefore God is not omnipotent.

Obj. 4: Further, upon the text, "God hath made foolish the wisdom of this world" (1 Cor. 1:20), a gloss says: "God hath made the wisdom of this world foolish [*Vulg.: 'Hath not God', etc.] by showing those things to be possible which it judges to be impossible." Whence it would seem that nothing is to be judged possible or impossible in reference to inferior causes, as the wisdom of this world judges them; but in reference to the divine power. If God, then, were omnipotent, all things would be possible; nothing, therefore impossible. But if we take away the impossible, then we destroy also the necessary; for what necessarily exists is impossible not to exist. Therefore there would be nothing at all that is necessary in things if God were omnipotent. But this is an impossibility. Therefore God is not omnipotent.

I answer that, All confess that God is omnipotent; but it seems difficult to explain in what His omnipotence precisely consists: for there may be doubt as to the precise meaning of the word 'all' when we say that God can do all things. If, however, we consider the matter aright, since power is said in reference to possible things, this phrase, "God can do all things," is rightly understood to mean that God can do all things that are possible; and for this reason He is said to be omnipotent. Now according to the Philosopher (Metaph. v, 17), a thing is said to be possible in two ways. First in relation to some power, thus whatever is subject to human power is said to be possible to man. Secondly absolutely, on account of the relation in which the very terms stand to each other. Now God cannot be said to be omnipotent through being able to do all things that are possible to created nature; for the divine power extends farther than that. If, however, we were to say that God is omnipotent because He can do all things that are possible to His power, there would be a vicious circle in explaining the nature of His power. For this would be saying nothing else but that God is omnipotent, because He can do all that He is able to do.

It remains therefore, that God is called omnipotent because He can do all things that are possible absolutely; which is the second way of saying a thing is possible. For a thing is said to be possible or impossible absolutely, according to the relation in which the very terms stand to one another, possible if the predicate is not incompatible with the subject, as that Socrates sits; and absolutely impossible when the predicate is altogether incompatible with the subject, as, for instance, that a man is a donkey.

It must, however, be remembered that since every agent produces an effect like itself, to each active power there corresponds a thing possible as its proper object according to the nature of that act on which its active power is founded; for instance, the power of giving warmth is related as to its proper object to the being capable of being warmed. The divine existence, however, upon which the nature of power in God is founded, is infinite, and is not limited to any genus of being; but possesses within itself the perfection of all being. Whence, whatsoever has or can have the nature of being, is numbered among the absolutely possible things, in respect of which God is called omnipotent. Now nothing is opposed to the idea of being except non-being. Therefore, that which implies being and non-being at the same time is repugnant to the idea of an absolutely possible thing, within the scope of the divine omnipotence. For such cannot come under the divine omnipotence, not because of any defect in the power of God, but because it has not the nature of a feasible or possible thing. Therefore, everything that does not imply a contradiction in terms, is numbered amongst those possible things, in respect of which God is called omnipotent: whereas whatever implies contradiction does not come within the scope of divine omnipotence, because it cannot have the aspect of possibility. Hence it is better to say that such things cannot be done, than that God cannot do them. Nor is this contrary to the word of the angel, saying: "No word shall be impossible with God."