It is, of course, now plain that of necessity that man was born from a Virgin Mother without natural seed.
 For the seed of the man is required in human generation as an active principle by reason of the active power in it. But the active power in the generation of the body of Christ could not be a natural power, in the light of the points we have seen. For the natural power does not of a sudden bring about the entire formation of the body, it requires time for this, but the body of Christ was in the first moment of conception formed and organized as was shown. Therefore, one concludes that the generation of Christ was without natural seed.
 Again, the male seed, in the generation of any animal at all, attracts to itself the matter supplied by the mother, as though the power which is in the male seed intends its own fulfillment as the end of the entire generation; hence, also, when the generation is completed, the seed itself, unchanged and fulfilled, is the offspring which is born. But the human generation of Christ had as ultimate term union with the divine Person, and not the establishment of a human person or hypostasis, as is clear from the foregoing. In this generation, therefore, the active principle could not be the seed of the man; it could only be the divine power. Just as the seed of the man in the common generation of men attracts to its subsistence the matter supplied by the mother, so this same matter in the generation the Word of God has assumed into union with Himself.
 In like manner, of course, it was manifestly suitable that, even in the human generation of the Word of God, some spiritual property of the generation of a word should shine out. Now, a word as it proceeds from a speaker—whether conceived within or expressed without—brings no corruption to the speaker, rather, the word marks the plenitude of perfection in the speaker. It was in harmony with this that in His human generation the Word of God should be so conceived and born that the wholeness of His Mother was not impaired. And this, too, is clear: It became the Word of God, by whom all things are established and by whom all things are preserved in His wholeness, to be born so as to preserve His Mother’s wholeness in every way. Therefore, suitably this generation was from a virgin.
 And for all that, this mode of generation detracts in nothing from the true and natural humanity of Christ, even though He was generated differently from other men. For clearly, since the divine power is infinite, as has been proved, and since through it all causes are granted the power to produce an effect, every effect whatever produced by every cause whatever can be produced by God without the assistance of that cause of the same species and nature. Then, just as the natural power which is in the human seed produces a true man who has the human species and nature, so the divine power, which gave such power to the seed, can without its power produce that effect by constituting a true man who has the human species and nature.
 But let someone object: a naturally generated man has a body naturally constituted from the seed of the male and what the female supplies—be that what it may; therefore, the body of Christ was not the same in nature as ours if it was not generated from the seed of a male. To this an answer may be made in accordance with a position of Aristotle, he says that the seed of the male does not enter materially into the constitution of what is conceived; it is an active principle only, whereas the entire matter of the body is supplied by the mother. Taken thus, in respect of matter the body of Christ does not differ from ours; for our bodies also are constituted materially of that which is taken from the mother.
 But, if one rejects the position of Aristotle just described, then the objection just described has no efficacy. For the likeness or unlikeness of things in matter is not marked off by the state of the matter in the principle of generation, but by the state of the matter already prepared as it is in the term of the generation. There is no difference in matter between air generated from earth and that from water, because, although water and earth are different in the principle of generation, they are nonetheless reduced by the generating action to one disposition. Thus, then, by the divine power the matter taken from the woman alone can be reduced at the end of the generation to a disposition identical with that which matter has if taken simultaneously from the male and female. Hence, there will be no unlikeness by reason of diversity of matter between the body of Christ which was formed by the divine power out of matter taken from the mother alone, and our bodies which are formed by the natural power from matter, even though they are taken from both parents. Surely this is clear; the matter taken simultaneously from a man and a woman and that “slime of the earth” (Gen. 2:7) of which God formed the first man (very certainly a true man and like us in everything) differ more from one another than from the matter taken solely from the female from which the body of Christ was formed. Hence, the birth of Christ from the Virgin does not at all diminish either the truth of His humanity or His likeness to us. For, although a natural power requires a determined matter for the production of a determined effect therefrom, the divine power, the power able to produce all things from nothing, is not in its activity circumscribed within determinate matter.
 In the same way, that she as a virgin conceived and gave birth diminishes not at all the dignity of the Mother of Christ—so that she be not the true and natural mother of the Son of God. For, while the divine power worked, she supplied the natural matter for the generation of the body of Christ-and this alone is required on the part of the mother; but the things which in other mothers contribute to the loss of virginity belong not to the process of being a mother, but to that of being a father, in order to have the male seed arrive at the place of generation.
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