Now the cause of this dissolution is evident from the illustration we have given of it. For since the senses have a close connection with what is gross and earthy, while the intellect is in its nature of a nobler and more exalted character than the movements involved in sensation, it follows that as, through the estimate which is made by the senses, there is an erroneous judgment as to what is morally good, and this error has wrought the effect of substantiating a contrary condition, that part of us which has thus been made useless is dissolved by its reception of this contrary.
Now the bearing of our illustration is as follows. We supposed that some vessel has been composed of clay, and then, for some mischief or other, filled with melted lead, which lead hardens and remains in a non-liquid state; then that the owner of the vessel recovers it, and, as he possesses the potter's art, pounds to bits the ware which held the lead, and then remoulds the vessel after its former pattern for his own special use, emptied now of the material which had been mixed with it: by a like process the maker of our vessel, now that wickedness has intermingled with our sentient part, I mean that connected with the body, will dissolve the material which has received the evil, and, re-moulding it again by the Resurrection without any admixture of the contrary matter, will recombine the elements into the vessel in its original beauty.
Now since both soul and body have a common bond of fellowship in their participation of the sinful affections, there is also an analogy between the soul's and body's death. For as in regard to the flesh we pronounce the separation of the sentient life to be death, so in respect of the soul we call the departure of the real life death. While, then, as we have said before, the participation in evil observable both in soul and body is of one and the same character, for it is through both that the evil principle advances into actual working, the death of dissolution which came from that clothing of dead skins does not affect the soul.
For how can that which is uncompounded be subject to dissolution? But since there is a necessity that the defilements which sin has engendered in the soul as well should be removed thence by some remedial process, the medicine which virtue supplies has, in the life that now is, been applied to the healing of such mutilations as these. If, however, the soul remains unhealed, the remedy is dispensed in the life that follows this. Now in the ailments of the body there are sundry differences, some admitting of an easier, others requiring a more difficult treatment.
In these last the use of the knife, or cauteries, or draughts of bitter medicines are adopted to remove the disease that has attacked the body. For the healing of the soul's sicknesses the future judgment announces something of the same kind, and this to the thoughtless sort is held out as the threat of a terrible correction, in order that through fear of this painful retribution they may gain the wisdom of fleeing from wickedness: while by those of more intelligence it is believed to be a remedial process ordered by God to bring back man, His peculiar creature, to the grace of his primal condition.
They who use the knife or cautery to remove certain unnatural excrescences in the body, such as wens or warts, do not bring to the person they are serving a method of healing that is painless, though certainly they apply the knife without any intention of injuring the patient. In like manner whatever material excrescences are hardening on our souls, that have been sensualized by fellowship with the body's affections, are, in the day of the judgment, as it were cut and scraped away by the ineffable wisdom and power of Him Who, as the Gospel says, “heals those that are sick.”
For, as He says again, “they that are whole have no need of the physician, but they that are sick.” Since, then, there has been inbred in the soul a strong natural tendency to evil, it must suffer, just as the excision of a wart gives a sharp pain to the skin of the body; for whatever contrary to the nature has been inbred in the nature attaches itself to the subject in a certain union of feeling, and hence there is produced an abnormal intermixture of our own with an alien quality, so that the feelings, when the separation from this abnormal growth comes, are hurt and lacerated.
Thus when the soul pines and melts away under the correction of its sins, as prophecy somewhere tells us, there necessarily follow, from its deep and intimate connection with evil, certain unspeakable and inexpressible pangs, the description of which is as difficult to render as is that of the nature of those good things which are the subjects of our hope. For neither the one nor the other is capable of being expressed in words, or brought within reach of the understanding. If, then, any one looks to the ultimate aim of the Wisdom of Him Who directs the economy of the universe, he would be very unreasonable and narrow-minded to call the Maker of man the Author of evil; or to say that He is ignorant of the future, or that, if He knows it and has made him, He is not uninfluenced by the impulse to what is bad.
He knew what was going to be, yet did not prevent the tendency towards that which actually happened. That humanity, indeed, would be diverted from the good, could not be unknown to Him Who grasps all things by His power of foresight, and Whose eyes behold the coming equally with the past events. As, then, He had in sight the perversion, so He devised man's recall to good. Accordingly, which was the better way?— never to have brought our nature into existence at all, since He foresaw that the being about to be created would fall away from that which is morally beautiful; or to bring him back by repentance, and restore his diseased nature to its original beauty?
But, because of the pains and sufferings of the body which are the necessary accidents of its unstable nature, to call God on that account the Maker of evil, or to think that He is not the Creator of man at all, in hopes thereby to prevent the supposition of His being the Author of what gives us pain—all this is an instance of that extreme narrow-mindedness which is the mark of those who judge of moral good and moral evil by mere sensation. Such persons do not understand that that only is intrinsically good which sensation does not reach, and that the only evil is estrangement from the good.
But to make pains and pleasures the criterion of what is morally good and the contrary, is a characteristic of the unreasoning nature of creatures in whom, from their want of mind and understanding, the apprehension of real goodness has no place. That man is the work of God, created morally noble and for the noblest destiny, is evident not only from what has been said, but from a vast number of other proofs; which, because they are so many, we shall here omit. But when we call God the Maker of man we do not forget how carefully at the outset we defined our position against the Greeks.
It was there shown that the Word of God is a substantial and personified being, Himself both God and the Word; Who has embraced in Himself all creative power, or rather Who is very power with an impulse to all good; Who works out effectually whatever He wills by having a power concurrent with His will; Whose will and work is the life of all things that exist; by Whom, too, man was brought into being and adorned with the highest excellences after the fashion of Deity. But since that alone is unchangeable in its nature which does not derive its origin through creation, while whatever by the uncreated being is brought into existence out of what was nonexistent, from the very first moment that it begins to be, is ever passing through change, and if it acts according to its nature the change is ever to the better, but if it be diverted from the straight path, then a movement to the contrary succeeds—since, I say, man was thus conditioned, and in him the changeable element in his nature had slipped aside to the exact contrary, so that this departure from the good introduced in its train every form of evil to match the good (as, for instance, on the defection of life there was brought in the antagonism of death; on the deprivation of light darkness supervened; in the absence of virtue vice arose in its place, and against every form of good might be reckoned a like number of opposite evils), by whom, I ask, was man, fallen by his recklessness into this and the like evil state (for it was not possible for him to retain even his prudence when he had estranged himself from prudence, or to take any wise counsel when he had severed himself from wisdom)—by whom was man to be recalled to the grace of his original state? To whom belonged the restoration of the fallen one, the recovery of the lost, the leading back the wanderer by the hand? To whom else than entirely to Him Who is the Lord of his nature? For Him only Who at the first had given the life was it possible, or fitting, to recover it when lost. This is what we are taught and learn from the Revelation of the truth, that God in the beginning made man and saved him when he had fallen.
Source: The Great Catechism (New Advent)