23 I must briefly mention the manner in which she avoided the foul cisterns of the heretics whom she regarded as no better than heathen. A certain cunning knave, in his own estimation both learned and clever, began without my knowledge to put to her such questions as these: What sin has an infant committed that it should be seized by the devil? Shall we be young or old when we rise again? If we die young and rise young, we shall after the resurrection require to have nurses.
If however we die young and rise old, the dead will not rise again at all: they will be transformed into new beings. Will there be a distinction of sexes in the next world? Or will there be no such distinction? If the distinction continues, there will be wedlock and sexual intercourse and procreation of children. If however it does not continue, the bodies that rise again will not be the same. For, he argued, “the earthy tabernacle weighs down the mind that muses upon many things,” but the bodies that we shall have in heaven will be subtle and spiritual according to the words of the apostle: “it is sown a natural body: it is raised a spiritual body.” From all of which considerations he sought to prove that rational creatures have been for their faults and previous sins subjected to bodily conditions; and that according to the nature and guilt of their transgression they are born in this or that state of life.
Some, he said, rejoice in sound bodies and wealthy and noble parents; others have for their portion diseased frames and poverty stricken homes; and by imprisonment in the present world and in bodies pay the penalty of their former sins. Paula listened and reported what she heard to me, at the same time pointing out the man. Thus upon me was laid the task of opposing this most noxious viper and deadly pest. It is of such that the Psalmist speaks when he writes: “deliver not the soul of your turtle dove unto the wild beast,” and “Rebuke the wild beast of the reeds;” creatures who write iniquity and speak lies against the Lord and lift up their mouths against the Most High.
As the fellow had tried to deceive Paula, I at her request went to him, and by asking him a few questions involved him in a dilemma. Do you believe, said I, that there will be a resurrection of the dead or do you disbelieve? He replied, I believe. I went on: Will the bodies that rise again be the same or different? He said, The same. Then I asked: What of their sex? Will that remain unaltered or will it be changed? At this question he became silent and swayed his head this way and that as a serpent does to avoid being struck.
Accordingly I continued, As you have nothing to say I will answer for you and will draw the conclusion from your premises. If the woman shall not rise again as a woman nor the man as a man, there will be no resurrection of the dead. For the body is made up of sex and members. But if there shall be no sex and no members what will become of the resurrection of the body, which cannot exist without sex and members? And if there shall be no resurrection of the body, there can be no resurrection of the dead.
But as to your objection taken from marriage, that, if the members shall remain the same, marriage must inevitably be allowed; it is disposed of by the Saviour's words: “ye do err not knowing the scriptures nor the power of God. For in the resurrection they neither marry nor are given in marriage but are as the angels.” When it is said that they neither marry nor are given in marriage, the distinction of sex is shown to persist. For no one says of things which have no capacity for marriage such as a stick or a stone that they neither marry nor are given in marriage; but this may well be said of those who while they can marry yet abstain from doing so by their own virtue and by the grace of Christ.
But if you cavil at this and say, how shall we in that case be like the angels with whom there is neither male nor female, hear my answer in brief as follows. What the Lord promises to us is not the nature of angels but their mode of life and their bliss. And therefore John the Baptist is called an angel even before he is beheaded, and all God's holy men and virgins manifest in themselves even in this world the life of angels. When it is said “you shall be like the angels,” likeness only is promised and not a change of nature.
Source: Letters (New Advent)