Thomas Aquinas, Summa Theologiae

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.

Objection 2: Further, if God is seen through a medium, He is not seen in His essence. But if seen by any created light, He is seen through a medium. Therefore He is not seen in His essence.

Objection 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.

On the contrary, It is written: "In Thy light we shall see light" (Ps. 35:10).

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 we shall see Him as He is" (1 Jn. 2:2).

Reply to Objection 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 to Objection 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 to Objection 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.

Articulus 5

Argumentum 1

Ad quintum sic proceditur. Videtur quod intellectus creatus ad videndum essentiam dei aliquo lumine creato non indigeat.

Illud enim quod est per se lucidum in rebus sensibilibus, alio lumine non indiget ut videatur, ergo nec in intelligibilibus.

Sed deus est lux intelligibilis.

Ergo non videtur per aliquod lumen creatum.

Argumentum 2

Praeterea, cum deus videtur per medium, non videtur per suam essentiam. Sed cum videtur per aliquod lumen creatum, videtur per medium. Ergo non videtur per suam essentiam.

Argumentum 3

Praeterea, illud quod est creatum, nihil prohibet alicui creaturae esse naturale. Si ergo per aliquod lumen creatum dei essentia videtur, poterit illud lumen esse naturale alicui creaturae. Et ita illa creatura non indigebit aliquo alio lumine ad videndum deum, quod est impossibile. Non est ergo necessarium quod omnis creatura ad videndum dei essentiam lumen superadditum requirat.

Sed Contra

Sed contra est quod dicitur in Psalmo, in lumine tuo videbimus lumen.

Corpus

Respondeo dicendum quod omne quod elevatur ad aliquid quod excedit suam naturam, oportet quod disponatur aliqua dispositione quae sit supra suam naturam, sicut, si aer debeat accipere formam ignis, oportet quod disponatur aliqua dispositione ad talem formam. Cum autem aliquis intellectus creatus videt deum per essentiam, ipsa essentia dei fit forma intelligibilis intellectus. Unde oportet quod aliqua dispositio supernaturalis ei superaddatur, ad hoc quod elevetur in tantam sublimitatem.

Cum igitur virtus naturalis intellectus creati non sufficiat ad dei essentiam videndam, ut ostensum est, oportet quod ex divina gratia superaccrescat ei virtus intelligendi. Et hoc augmentum virtutis intellectivae illuminationem intellectus vocamus; sicut et ipsum intelligibile vocatur lumen vel lux.

Et istud est lumen de quo dicitur Apoc. XXI, quod claritas dei illuminabit eam, scilicet societatem beatorum deum videntium. Et secundum hoc lumen efficiuntur deiformes, idest deo similes; secundum illud I Ioan. III, cum apparuerit, similes ei erimus, et videbimus eum sicuti est.

Ad 1

Ad primum ergo dicendum quod lumen creatum est necessarium ad videndum dei essentiam, non quod per hoc lumen dei essentia intelligibilis fiat, quae secundum se intelligibilis est, sed ad hoc quod intellectus fiat potens ad intelligendum, per modum quo potentia fit potentior ad operandum per habitum, sicut etiam et lumen corporale necessarium est in visu exteriori, inquantum facit medium transparens in actu, ut possit moveri a colore.

Ad 2

Ad secundum dicendum quod lumen istud non requiritur ad videndum dei essentiam quasi similitudo in qua deus videatur, sed quasi perfectio quaedam intellectus, confortans ipsum ad videndum deum. Et ideo potest dici quod non est medium in quo deus videatur, sed sub quo videtur. Et hoc non tollit immediatam visionem dei.

Ad 3

Ad tertium dicendum quod dispositio ad formam ignis non potest esse naturalis nisi habenti formam ignis. Unde lumen gloriae non potest esse naturale creaturae, nisi creatura esset naturae divinae, quod est impossibile. Per hoc enim lumen fit creatura rationalis deiformis, ut dictum est.