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

Reply Obj. 3: The divine essence is existence itself. Hence as other intelligible forms which are not their own existence are united to the intellect by means of some entity, whereby the intellect itself is informed, and made in act; so the divine essence is united to the created intellect, as the object actually understood, making the intellect in act by and of itself. _______________________

Obj. 2: Further, Augustine says (De Civ. Dei xxix, 29): "Those eyes" (namely the glorified) "will therefore have a greater power of sight, not so much to see more keenly, as some report of the sight of serpents or of eagles (for whatever acuteness of vision is possessed by these creatures, they can see only corporeal things) but to see even incorporeal things." Now whoever can see incorporeal things, can be raised up to see God. Therefore the glorified eye can see God.

Obj. 3: Further, God can be seen by man through a vision of the imagination. For it is written: "I saw the Lord sitting upon a throne," etc. (Isa. 6:1). But an imaginary vision originates from sense; for the imagination is moved by sense to act. Therefore God can be seen by a vision of sense.

I answer that, It is impossible for God to be seen by the sense of sight, or by any other sense, or faculty of the sensitive power. For every such kind of power is the act of a corporeal organ, as will be shown later (Q. 78). Now act is proportional to the nature which possesses it. Hence no power of that kind can go beyond corporeal things. For God is incorporeal, as was shown above (Q. 3, A. 1). Hence He cannot be seen by the sense or the imagination, but only by the intellect.

Reply Obj. 1: The words, "In my flesh I shall see God my Saviour," do not mean that God will be seen with the eye of the flesh, but that man existing in the flesh after the resurrection will see God. Likewise the words, "Now my eye seeth Thee," are to be understood of the mind's eye, as the Apostle says: "May He give unto you the spirit of wisdom . . . in the knowledge of Him, that the eyes of your heart" may be "enlightened" (Eph. 1:17, 18).

Reply Obj. 2: Augustine speaks as one inquiring, and conditionally. This appears from what he says previously: "Therefore they will have an altogether different power (viz. the glorified eyes), if they shall see that incorporeal nature;" and afterwards he explains this, saying: "It is very credible, that we shall so see the mundane bodies of the new heaven and the new earth, as to see most clearly God everywhere present, governing all corporeal things, not as we now see the invisible things of God as understood by what is made; but as when we see men among whom we live, living and exercising the functions of human life, we do not believe they live, but see it." Hence it is evident how the glorified eyes will see God, as now our eyes see the life of another. But life is not seen with the corporeal eye, as a thing in itself visible, but as the indirect object of the sense; which indeed is not known by sense, but at once, together with sense, by some other cognitive power. But that the divine presence is known by the intellect immediately on the sight of, and through, corporeal things, happens from two causes—viz. from the perspicuity of the intellect, and from the refulgence of the divine glory infused into the body after its renovation.

Reply Obj. 3: The essence of God is not seen in a vision of the imagination; but the imagination receives some form representing God according to some mode of similitude; as in the divine Scripture divine things are metaphorically described by means of sensible things. _______________________

Objection 1: It seems that a created intellect can see the Divine essence by its own natural power. For Dionysius says (Div. Nom. iv): "An angel is a pure mirror, most clear, receiving, if it is right to say so, the whole beauty of God." But if a reflection is seen, the original thing is seen. Therefore since an angel by his natural power understands himself, it seems that by his own natural power he understands the Divine essence.

Obj. 2: Further, what is supremely visible, is made less visible to us by reason of our defective corporeal or intellectual sight. But the angelic intellect has no such defect. Therefore, since God is supremely intelligible in Himself, it seems that in like manner He is supremely so to an angel. Therefore, if he can understand other intelligible things by his own natural power, much more can he understand God.

Obj. 3: Further, corporeal sense cannot be raised up to understand incorporeal substance, which is above its nature. Therefore if to see the essence of God is above the nature of every created intellect, it follows that no created intellect can reach up to see the essence of God at all. But this is false, as appears from what is said above (A. 1). Therefore it seems that it is natural for a created intellect to see the Divine essence.

On the contrary, It is written: "The grace of God is life everlasting" (Rom. 6:23). But life everlasting consists in the vision of the Divine essence, according to the words: "This is eternal life, that they may know Thee the only true God," etc. (John 17:3). Therefore to see the essence of God is possible to the created intellect by grace, and not by nature.

I answer that, It is impossible for any created intellect to see the essence of God by its own natural power. For knowledge is regulated according as the thing known is in the knower. But the thing known is in the knower according to the mode of the knower. Hence the knowledge of every knower is ruled according to its own nature. If therefore the mode of anything's being exceeds the mode of the knower, it must result that the knowledge of the object is above the nature of the knower. Now the mode of being of things is manifold. For some things have being only in this one individual matter; as all bodies. But others are subsisting natures, not residing in matter at all, which, however, are not their own existence, but receive it; and these are the incorporeal beings, called angels. But to God alone does it belong to be His own subsistent being. Therefore what exists only in individual matter we know naturally, forasmuch as our soul, whereby we know, is the form of certain matter. Now our soul possesses two cognitive powers; one is the act of a corporeal organ, which naturally knows things existing in individual matter; hence sense knows only the singular. But there is another kind of cognitive power in the soul, called the intellect; and this is not the act of any corporeal organ.

Wherefore the intellect naturally knows natures which exist only in individual matter; not as they are in such individual matter, but according as they are abstracted therefrom by the considering act of the intellect; hence it follows that through the intellect we can understand these objects as universal; and this is beyond the power of the sense. Now the angelic intellect naturally knows natures that are not in matter; but this is beyond the power of the intellect of our soul in the state of its present life, united as it is to the body. It follows therefore that to know self-subsistent being is natural to the divine intellect alone; and this is beyond the natural power of any created intellect; for no creature is its own existence, forasmuch as its existence is participated. Therefore the created intellect cannot see the essence of God, unless God by His grace unites Himself to the created intellect, as an object made intelligible to it.

Reply Obj. 1: This mode of knowing God is natural to an angel—namely, to know Him by His own likeness refulgent in the angel himself. But to know God by any created similitude is not to know the essence of God, as was shown above (A. 2). Hence it does not follow that an angel can know the essence of God by his own power.

Reply Obj. 2: The angelic intellect is not defective, if defect be taken to mean privation, as if it were without anything which it ought to have. But if the defect be taken negatively, in that sense every creature is defective, when compared with God; forasmuch as it does not possess the excellence which is in God.

Reply Obj. 3: The sense of sight, as being altogether material, cannot be raised up to immateriality. But our intellect, or the angelic intellect, inasmuch as it is elevated above matter in its own nature, can be raised up above its own nature to a higher level by grace. The proof is, that sight cannot in any way know abstractedly what it knows concretely; for in no way can it perceive a nature except as this one particular nature; whereas our intellect is able to consider abstractedly what it knows concretely. Now although it knows things which have a form residing in matter, still it resolves the composite into both of these elements; and it considers the form separately by itself. Likewise, also, the intellect of an angel, although it naturally knows the concrete in any nature, still it is able to separate that existence by its intellect; since it knows that the thing itself is one thing, and its existence is another. Since therefore the created intellect is naturally capable of apprehending the concrete form, and the concrete being abstractedly, by way of a kind of resolution of parts; it can by grace be raised up to know separate subsisting substance, and separate subsisting existence. _______________________

Objection 1: It seems that the created intellect does not need any created light in order to see the essence of God. For what is of itself lucid in sensible things does not require any other light in order to be seen. Therefore the same applies to intelligible things. Now God is intelligible light. Therefore He is not seen by means of any created light.

Obj. 3: Further, what is created can be natural to some creature. Therefore if the essence of God is seen through any created light, such a light can be made natural to some other creature; and thus, that creature would not need any other light to see God; which is impossible. Therefore it is not necessary that every creature should require a superadded light in order to see the essence of God.

I answer that, Everything which is raised up to what exceeds its nature, must be prepared by some disposition above its nature; as, for example, if air is to receive the form of fire, it must be prepared by some disposition for such a form. But when any created intellect sees the essence of God, the essence of God itself becomes the intelligible form of the intellect. Hence it is necessary that some supernatural disposition should be added to the intellect in order that it may be raised up to such a great and sublime height. Now since the natural power of the created intellect does not avail to enable it to see the essence of God, as was shown in the preceding article, it is necessary that the power of understanding should be added by divine grace. Now this increase of the intellectual powers is called the illumination of the intellect, as we also call the intelligible object itself by the name of light of illumination. And this is the light spoken of in the Apocalypse (Apoc. 21:23): "The glory of God hath enlightened it"—viz. the society of the blessed who see God. By this light the blessed are made "deiform"—i.e. like to God, according to the saying: "When He shall appear we shall be like to Him, and [Vulg.: 'because'] we shall see Him as He is" (1 John 2:2).

Reply Obj. 1: The created light is necessary to see the essence of God, not in order to make the essence of God intelligible, which is of itself intelligible, but in order to enable the intellect to understand in the same way as a habit makes a power abler to act. Even so corporeal light is necessary as regards external sight, inasmuch as it makes the medium actually transparent, and susceptible of color.

Reply Obj. 2: This light is required to see the divine essence, not as a similitude in which God is seen, but as a perfection of the intellect, strengthening it to see God. Therefore it may be said that this light is to be described not as a medium in which God is seen, but as one by which He is seen; and such a medium does not take away the immediate vision of God.

Reply Obj. 3: The disposition to the form of fire can be natural only to the subject of that form. Hence the light of glory cannot be natural to a creature unless the creature has a divine nature; which is impossible. But by this light the rational creature is made deiform, as is said in this article. _______________________

Objection 1: It seems that of those who see the essence of God, one does not see more perfectly than another. For it is written (1 John 3:2): "We shall see Him as He is." But He is only in one way. Therefore He will be seen by all in one way only; and therefore He will not be seen more perfectly by one and less perfectly by another.

Obj. 2: Further, Augustine says (Octog. Tri. Quaest. qu. xxxii): "One person cannot see one and the same thing more perfectly than another." But all who see the essence of God, understand the Divine essence, for God is seen by the intellect and not by sense, as was shown above (A. 3). Therefore of those who see the divine essence, one does not see more clearly than another.

Obj. 3: Further, That anything be seen more perfectly than another can happen in two ways: either on the part of the visible object, or on the part of the visual power of the seer. On the part of the object, it may so happen because the object is received more perfectly in the seer, that is, according to the greater perfection of the similitude; but this does not apply to the present question, for God is present to the intellect seeing Him not by way of similitude, but by His essence. It follows then that if one sees Him more perfectly than another, this happens according to the difference of the intellectual power; thus it follows too that the one whose intellectual power is higher, will see Him the more clearly; and this is incongruous; since equality with angels is promised to men as their beatitude.

On the contrary, Eternal life consists in the vision of God, according to John 17:3: "This is eternal life, that they may know Thee the only true God," etc. Therefore if all saw the essence of God equally in eternal life, all would be equal; the contrary to which is declared by the Apostle: "Star differs from star in glory" (1 Cor. 15:41).

I answer that, Of those who see the essence of God, one sees Him more perfectly than another. This, indeed, does not take place as if one had a more perfect similitude of God than another, since that vision will not spring from any similitude; but it will take place because one intellect will have a greater power or faculty to see God than another. The faculty of seeing God, however, does not belong to the created intellect naturally, but is given to it by the light of glory, which establishes the intellect in a kind of "deiformity," as appears from what is said above, in the preceding article.