Come now, if some philosopher affirms, as Laberius holds, following an opinion of Pythagoras, that a man may have his origin from a mule, a serpent from a woman, and with skill of speech twists every argument to prove his view, will he not gain acceptance for and work in some the conviction that, on account of this, they should even abstain from eating animal food? May any one have the persuasion that he should so abstain, lest by chance in his beef he eats of some ancestor of his?
But if a Christian promises the return of a man from a man, and the very actual Gaius from Gaius, the cry of the people will be to have him stoned; they will not even so much as grant him a hearing. If there is any ground for the moving to and fro of human souls into different bodies, why may they not return into the very substance they have left, seeing this is to be restored, to be that which had been? They are no longer the very things they had been; for they could not be what they were not, without first ceasing to be what they had been.
If we were inclined to give all rein upon this point, discussing into what various beasts one and another might probably be changed, we would need at our leisure to take up many points. But this we would do chiefly in our own defence, as setting forth what is greatly worthier of belief, that a man will come back from a man— any given person from any given person, still retaining his humanity; so that the soul, with its qualities unchanged, may be restored to the same condition, thought not to the same outward framework.
Assuredly, as the reason why restoration takes place at all is the appointed judgment, every man must needs come forth the very same who had once existed, that he may receive at God's hands a judgment, whether of good desert or the opposite. And therefore the body too will appear; for the soul is not capable of suffering without the solid substance (that is, the flesh; and for this reason, also) that it is not right that souls should have all the wrath of God to bear: they did not sin without the body, within which all was done by them.
But how, you say, can a substance which has been dissolved be made to reappear again? Consider yourself, O man, and you will believe in it! Reflect on what you were before you came into existence. Nothing. For if you had been anything, you would have remembered it. You, then, who were nothing before you existed, reduced to nothing also when you cease to be, why may you not come into being again out of nothing, at the will of the same Creator whose will created you out of nothing at the first?
Will it be anything new in your case? You who were not, were made; when you cease to be again, you shall be made. Explain, if you can, your original creation, and then demand to know how you shall be re-created. Indeed, it will be still easier surely to make you what you were once, when the very same creative power made you without difficulty what you never were before. There will be doubts, perhaps, as to the power of God, of Him who hung in its place this huge body of our world, made out of what had never existed, as from a death of emptiness and inanity, animated by the Spirit who quickens all living things, its very self the unmistakable type of the resurrection, that it might be to you a witness— nay, the exact image of the resurrection.
Light, every day extinguished, shines out again; and, with like alternation, darkness succeeds light's outgoing. The defunct stars re-live; the seasons, as soon as they are finished, renew their course; the fruits are brought to maturity, and then are reproduced. The seeds do not spring up with abundant produce, save as they rot and dissolve away—all things are preserved by perishing, all things are refashioned out of death. You, man of nature so exalted, if you understand yourself, taught even by the Pythian words, lord of all these things that die and rise,— shall you die to perish evermore?
Wherever your dissolution shall have taken place, whatever material agent has destroyed you, or swallowed you up, or swept you away, or reduced you to nothingness, it shall again restore you. Even nothingness is His who is Lord of all. You ask, Shall we then be always dying, and rising up from death? If so the Lord of all things had appointed, you would have to submit, though unwillingly, to the law of your creation. But, in fact, He has no other purpose than that of which He has informed us.
The Reason which made the universe out of diverse elements, so that all things might be composed of opposite substances in unity— of void and solid, of animate and inanimate, of comprehensible and incomprehensible, of light and darkness, of life itself and death— has also disposed time into order, by fixing and distinguishing its mode, according to which this first portion of it, which we inhabit from the beginning of the world, flows down by a temporal course to a close; but the portion which succeeds, and to which we look forward continues forever.
When, therefore, the boundary and limit, that millennial interspace, has been passed, when even the outward fashion of the world itself— which has been spread like a veil over the eternal economy, equally a thing of time— passes away, then the whole human race shall be raised again, to have its dues meted out according as it has merited in the period of good or evil, and thereafter to have these paid out through the immeasurable ages of eternity. Therefore after this there is neither death nor repeated resurrections, but we shall be the same that we are now, and still unchanged— the servants of God, ever with God, clothed upon with the proper substance of eternity; but the profane, and all who are not true worshippers of God, in like manner shall be consigned to the punishment of everlasting fire— that fire which, from its very nature indeed, directly ministers to their incorruptibility.
The philosophers are familiar as well as we with the distinction between a common and a secret fire. Thus that which is in common use is far different from that which we see in divine judgments, whether striking as thunderbolts from heaven, or bursting up out of the earth through mountain-tops; for it does not consume what it scorches, but while it burns it repairs. So the mountains continue ever burning; and a person struck by lighting is even now kept safe from any destroying flame. A notable proof this of the fire eternal! A notable example of the endless judgment which still supplies punishment with fuel! The mountains burn, and last. How will it be with the wicked and the enemies of God?
Source: The Apology (New Advent)