Eran.— Unquestionably.
Orth.— Then the nature of the iron was not damaged by contact with the fire. If then, in natural bodies, instances may be found of an unconfounded mixture, it is sheer folly in the case of the nature which knows neither corruption nor change to entertain the idea of confusion and destruction of the assumed nature, and all the more so when this nature was assumed to bring blessing on the race.
Eran.— What I assert is not the destruction of the assumed nature, but its change into the substance of Godhead.
Orth.— Then the human race is no longer limited as heretofore?
Eran.— No.
Orth.— When did it undergo this change?
Eran.— After the complete union.
Orth.— And what date do you assign to this?
Eran.— I have said again and again, that of the conception.
Orth.— Yet after the conception He was an unborn babe in the womb; after His birth. He was a babe and was called a babe, and was worshipped by shepherds, and in like manner became a boy, and was so called by the angel. Do you acknowledge all this? Or do you think I am inventing fables?
Eran.— This is taught in the history of the divine gospels, and cannot be gainsaid.
Orth.— Now let us investigate what follows. We acknowledge, do we not, that the Lord was circumcised?
Eran.— Yes.
Orth.— Of what was there a circumcision? Of flesh or Godhead?
Eran.— Of the flesh.
Orth.— Of what was then the growth and increase in wisdom and stature?
Eran.— This, of course, is not applicable to Godhead.
Orth.— Nor hunger and thirst?
Eran.— No.
Orth.— Nor walking about, and being weary, and falling asleep?
Eran.— No.
Orth.— If then the union took place at the conception, and all these things came to pass after the conception and the birth, then, after the union, the manhood did not lose its own nature.
Eran.— I have not stated my meaning exactly. It was after the resurrection from the dead that the flesh underwent the change into Godhead.
Orth.— Then, after the resurrection, nothing of all that indicates its nature remained in it?
Eran.— If it remained, the divine change did not take place.
Orth.— How then was it that He showed His hands and His feet to the disciples who disbelieved?
Eran.— Just as He came in when the doors were shut.
Orth.— But He came in when the doors were shut just as He came out from the womb, though the virgin's bolts and bars were undrawn, and just as He walked upon the sea. Then according to your argument not even yet had the change of nature taken place?
Eran.— The Lord showed His hands to the Apostles in the same way as He wrestled with Jacob.
Orth.— No; the Lord does not allow us to understand it in this sense. The disciples thought they saw a spirit, but the Lord dispelled this idea, and showed the nature of the flesh, for He said “Why are you troubled? And why do thoughts arise in your hearts? Behold my hands and my feet, that it is I myself: handle me, and see; for a spirit has not flesh and bones, as you see me have.” And observe the exactness of the language. He does not say “is not flesh and bones,” but “has not flesh and bones,” in order to point out that the nature of the possessor and the nature of that which is possessed are distinct and separate. Just in the same way that which took and that which was taken are separate and distinct, and the Christ is beheld made one of both. Thus the part possessing is entirely different from the part possessed; and yet does not divide into two persons Him who is an object of thought in them. The Lord, indeed, while the disciples were still in doubt, asked for food and took and ate it, not consuming the food only in appearance, nor satisfying to the need of the body.
Eran.— But one of these alternatives must be accepted; either He partook because He needed, or else, needing not, He seemed to eat, and did not really partake of food.
Orth.— His body now become immortal required no food. Of them that rise the Lord says: “they neither marry nor are given in marriage but are as Angels.” The apostles however bear witness that He partook of the food, for the blessed Luke in the preface to the Acts says “being assembled together with the apostles the Lord commanded them that they should not depart from Jerusalem” and the very divine Peter says more distinctly: “Who ate and drank with Him after He rose from the dead.” For since eating is proper to them that live this present life, of necessity the Lord by means of eating and drinking proved the resurrection of the flesh to them that did not acknowledge it to be real. This same course He pursued in the case of Lazarus and of Jairus' daughter. For when He had raised up the latter He ordered that something should be given her to eat and He made Lazarus sit with Him at the table and so showed the reality of the rising again.
Eran.— If we grant that the Lord really ate, let us grant that after the resurrection all men partake of food.
Orth.— What was done by the Saviour through a certain œconomy is not a rule and law of nature. This follows from the fact that He did other things by œconomy which shall by no means be the lot of them that live again.
Eran.— What do you mean?
Orth.— Will not the bodies of them that rise become incorruptible and immortal?
Eran.— So the divine Paul has taught us. “It is sown” he says “in corruption; it is raised in incorruption; it is sown in dishonour; it is raised in glory; it is sown in weakness; it is raised in power; it is sown a natural body; it is raised a spiritual body.”
Orth.— But the Lord, who raises the bodies of all men, unmaimed and unmarred (for lameness of limb and blindness of eye are unknown among them that are risen), left in His own body the prints of the nails, and the wound in His side, whereof are witnesses both the Lord Himself and the hand of Thomas.
Eran.— True.
Orth.— If then after the resurrection the Lord both partook of food, and showed His hands and His feet to His disciples, and in them the prints of the nails, and His side with the mark of the wound in it, and said to them, “Handle me and see for a spirit has not flesh and bones as you see me have” it follows that after His resurrection the nature of His body was preserved and was not changed into another substance.
Eran.— Then after the resurrection it is mortal and subject to suffering?
Orth.— By no means; it is incorruptible, impassible, and immortal.
Eran.— If it is incorruptible, impassible, and immortal, it has been changed into another nature.
Orth.— Therefore the bodies of all men will be changed into another substance, for all will be incorruptible and immortal. Or have you not heard the words of the Apostle, “For this corruptible must put on incorruption, and this mortal must put on immortality”?
Eran.— I have heard.
Orth.— Therefore the nature remains, but its corruption is changed into incorruption, and its mortal into immortality. But let us look at the matter in this way; we call a body that is sick and a body that is whole, in the same way, a body.
Eran.— Unquestionably.
Orth.— Wherefore?
Eran.— Since both partake of the same substance.
Orth.— Yet we see in them a very great difference, for the one is whole, perfect, and unhurt; the other has either lost an eye, or has a broken leg, or has undergone some other suffering.
Eran.— But to the same nature belong both health and sickness.
Orth.— So the body is called substance; disease and health are called accident.
Eran.— Of course. For these things are accidents of the body, and again cease to be so.
Orth.— In the same way corruption and death must be called accidents, and not substances, for they too are accidents and cease to be so.
Eran.— True.
Orth.— So the body of the Lord rose incorruptible, impassible, and immortal, and is worshipped by the powers of heaven, and is yet a body having its former limitation.
Source: Dialogues ("Eranistes" or "Polymorphus") (New Advent)