Objection 1. It would seem that the resurrection is natural. For, as the Damascene says (De Fide Orth. iii, 14), "that which is commonly observed in all, marks the nature of the individuals contained under it." Now resurrection applies commonly to all. Therefore it is natural.
Objection 2. Further, Gregory says (Moral. xiv, 55): "Those who do not hold the resurrection on the principle of obedience ought certainly to hold it on the principle of reason. For what does the world every day but imitate, in its elements, our resurrection?" And he offers as examples the light which "as it were dies... and is withdrawn from our sight... and again rises anew, as it were, and is recalled--the shrubs which lose their greenery, and again by a kind of resurrection are renewed--and the seeds which rot and die and then sprout and rise again as it were": which same example is adduced by the Apostle (1 Corinthians 15:36). Now from the works of nature nothing can be known save what is natural. Therefore the resurrection is natural.
Objection 3. Further, things that are against nature abide not for long, because they are violent, so to speak. But the life that is restored by the resurrection will last for ever. Therefore the resurrection will be natural.
Objection 4. Further, that to which the entire expectation of nature looks forward would seem to be natural. Now such a thing is the resurrection and the glorification of the saints according to Romans 8:19. Therefore the resurrection will be natural.
Objection 5. Further, the resurrection is a kind of movement towards the everlasting union of soul and body. Now movement is natural if it terminate in a natural rest (Phys. v, 6): and the everlasting union of soul and body will be natural, for since the soul is the body's proper mover, it has a body proportionate to it: so that the body is likewise for ever capable of being quickened by it, even as the soul lives for ever. Therefore the resurrection will be natural.
On the contrary, There is no natural return from privation to habit. But death is privation of life. Therefore the resurrection whereby one returns from death to life is not natural.
Further, things of the one species have one fixed way of origin: wherefore animals begotten of putrefaction are never of the same species as those begotten of seed, as the Commentator says on Phys. viii. Now the natural way of man's origin is for him to be begotten of a like in species: and such is not the case in the resurrection. Therefore it will not be natural.
I answer that, A movement or an action stands related to nature in three ways. For there is a movement or action whereof nature is neither the principle nor the term: and such a movement is sometimes from a principle above nature as in the case of a glorified body; and sometimes from any other principle whatever; for instance, the violent upward movement of a stone which terminates in a violent rest. Again, there is a movement whereof nature is both principle and term: for instance, the downward movement of a stone. And there is another movement whereof nature is the term, but not the principle, the latter being sometimes something above nature (as in giving sight to a blind man, for sight is natural, but the principle of the sight-giving is above nature), and sometimes something else, as in the forcing of flowers or fruit by artificial process. It is impossible for nature to be the principle and not the term, because natural principles are appointed to definite effects, beyond which they cannot extend.
Accordingly the action or movement that is related to nature in the first way can nowise be natural, but is either miraculous if it come from a principle above nature, or violent if from any other principle. The action or movement that is related to nature in the second way is simply natural: but the action that is related to nature in the third way cannot be described as natural simply, but as natural in a restricted sense, in so far, to wit, as it leads to that which is according to nature: but it is called either miraculous or artificial or violent. For, properly speaking, natural is that which is according to nature, and a thing is according to nature if it has that nature and whatever results from that nature (Phys. ii, 1). Consequently, speaking simply, movement cannot be described as natural unless its principle be natural.
Now nature cannot be the principle of resurrection, although resurrection terminates in the life of nature. For nature is the principle of movement in the thing wherein nature is--either the active principle, as in the movement of heavy and light bodies and in the natural alterations of animals--or the passive principle, as in the generation of simple bodies. The passive principle of natural generation is the natural passive potentiality which always has an active principle corresponding to it in nature, according to Metaphysics viii, 1: nor as to this does it matter whether the active principle in nature correspond to the passive principle in respect of its ultimate perfection, namely the form; or in respect of a disposition in virtue of which it demands the ultimate form, as in the generation of a man according to the teaching of faith, or in all other generations according to the opinions of Plato and Avicenna. But in nature there is no active principle of the resurrection, neither as regards the union of the soul with the body, nor as regards the disposition which is the demand for that union: since such a disposition cannot be produced by nature, except in a definite way by the process of generation from seed. Wherefore even granted a passive potentiality on the part of the body, or any kind of inclination to its union with the soul, it is not such as to suffice for the conditions of natural movement. Therefore the resurrection, strictly speaking, is miraculous and not natural except in a restricted sense, as we have explained.
Reply to Objection 1. Damascene is speaking of those things that are found in all individuals and are caused by the principles of nature. For supposing by a divine operation all men to be made white, or to be gathered together in one place, as happened at the time of the deluge, it would not follow that whiteness or existence in some particular place is a natural property of man.
Reply to Objection 2. From natural things one does not come by a demonstration of reason to know non-natural things, but by the induction of reason one may know something above nature, since the natural bears a certain resemblance to the supernatural. Thus the union of soul and body resembles the union of the soul with God by the glory of fruition, as the Master says (Sent. ii, D, 1): and in like manner the examples, quoted by the Apostle and Gregory, are confirmatory evidences of our faith in the resurrection.
Reply to Objection 3. This argument regards an operation which terminates in something that is not natural but contrary to nature. Such is not the resurrection, and hence the argument is not to the point.
Reply to Objection 4. The entire operation of nature is subordinate to the Divine operation, just as the working of a lower art is subordinate to the working of a higher art. Hence just as all the work of a lower art has in view an end unattainable save by the operation of the higher art that produces the form, or makes use of what has been made by art: so the last end which the whole expectation of nature has in view is unattainable by the operation of nature, and for which reason the attaining thereto is not natural.
Reply to Objection 5. Although there can be no natural movement terminating in a violent rest, there can be a non-natural movement terminating in a natural rest, as explained above.
Source: Summa Theologica (New Advent)