Others, indeed, have avoided this position by reason of the awkwardness described above. They have held that soul and flesh in our Lord Jesus Christ constitutes one substance, namely, a certain man of the same species as other men. They call this man united to the Word of God, not in nature, indeed, but in person, so that there is one person of the Word of God and of that man. But, since that man is a kind of individual substance—and this is to be an hypostasis and supposit—some say that in Christ the hypostasis and supposit of that man is one and that of the Word of God another, but that there is one person of each of the two. On account of this unity, the Word of God, as they say, is predicated of that man and that man of the Word of God. This sense results: “The Word of God is man,” and that is: “The person of the Word of God is the person of the man,” and conversely. And in this account whatever is predicated of the Word of God is, they say, able to be predicated of that man; and, conversely, although with a kind of reduplication, so that when it is said “God has suffered,” the sense is “A man who is God by unity of person has suffered,” and “A man created the stars” means “He who is man.”
 But, of necessity, this position lapses into the error of Nestorius. For, if the difference of person and hypostasis be marked, one finds that person is not foreign to hypostasis, but a kind of part of hypostasis. For a person is nothing else than a hypostasis of a certain nature; namely, rational. This is clear from Boethius’ definition: “person is the individual substance of a rational nature.” Clearly, then, although not every hypostasis is a person, every hypostasis of human nature is, nonetheless, a person. If, therefore, from the mere union of soul and body in Christ there is constituted a certain particular substance which is the hypostasis-namely, that man-it follows that from the same union a person is constituted. There will be, then, in Christ two persons: one, and newly constituted, of that man; the other, eternal, of the Word of God. And this belongs to the Nestorian impiety.
 Again, even if the hypostasis of that man could not be called a person, the hypostasis of the Word of God is nonetheless the same as His Person. If, therefore, the hypostasis of the Word of God is not that of the man, neither will the Person Of the Word of God be the person of the man. This will falsify their own assertion that the person of that man is the Person of the Word of God.
 If one were to grant, further, that person is other than the hypostasis of God’s Word or of the man, one could find no difference save one: person adds some property to hypostasis. Nothing, of course, pertaining to the genus of substance can he added, since hypostasis is the most complete thing in the genus of substance, and it is called “first substance.” If, then, the union is made in person and not in hypostasis, it follows that the union takes place only according to some accidental property. This, too, comes again back to the error of Nestorius.
 Cyril, moreover, in his letter to Nestorius approved by the Council of Ephesus, has this to say: “If anyone does not confess that the Word from the Father is united to the flesh in subsistence, that Christ is one with his flesh, that is to say, that the same one is God and man at the same time, let him be anathema.” And almost everywhere in the synodal writings this is assigned as the error of Nestorius, who put two bypostases in Christ.
 Damascene, moreover, in Book III, says: “It was from a two perfect natures, we say, that the union took place, and not in a prosopic,” that is, personal way, “as God’s enemy Nestorius says, but according to the hypostasis.” Thus, clearly and expressly, this was the position of Nestorius: to confess one person and two hypostases.
 Again, hypostasis and supposit must be identified. Everything else is predicated of the first substance, which is the hypostasis: namely, the universals in the genus of substance as well as accidents, as the Philosopher says in his Categories . If, therefore, there are not two hypostases in Christ, neither are there two supposits.
 If the Word and that man, furthermore, differ in supposit, it must be that when that man is supposed the Word of God is not supposed, nor is the converse true. But, if the supposits are distinct, what is said of them must be distinguished, for the divine predicates mentioned are disproportionate to the man’s supposit except by reason of the Word; and the converse is true. Therefore, one must take separately the things said of Christ in Scripture; namely, the divine and the human. And this is contrary to the opinion of Cyril confirmed by the Synod: “If one divides between two persons or subsistences the words said in the evangelical and apostolic Scriptures-whether they be said about Christ by the saints, or by Him about Himself, and marks off some of them, indeed, as for a man especially understood alongside that Word from God, and marks off others as capable of being said by God, for that Word from God the Father alone: let him be anathema.”
 Moreover, in the position described, things proportioned to the Word of God by nature would not be said of that man except by a certain association in one person; this is what -the interposed reduplication means when they expound thus: “That man created the stars,” that is, “the Son of God, who is that man,” and similarly with others of that sort. Hence, when one says: “That man is God,” one understands it thus: “That man exists by the Word of God.” But it is this kind of expression that Cyril condemns when he says: “If anyone dares to say that the man assumed ought to be co-adored with God’s Word, co-glorified, and co-named God, a second of two with the first, so to speak (for that is what “co” forces us to understand as often as it is added), and does not honor Emmanuel with one adoration and offer Him one glorification, inasmuch as the Word was made flesh; let him be anathema.”
 There is more. If that man is other than the Word in supposit, he cannot belong to the person of the Word except by the assumption by which He was assumed by the Word. But this is foreign to a correct understanding of the faith, for the Council of Ephesus says in the words of Felix, Pope and martyr: “We believe in God our Jesus, born of the Virgin Mary: that He is God’s everlasting Son and Word, and not a an assumed by God so that there is another beside Him. Nor did God’s Son assume a man that there be another beside Him; but the perfect existing God was made at the same time perfect man, made flesh of the Virgin.”
 Again, things which are many in supposit are many simply, and they are but incidentally one. If, then, in Christ there are two supposits, it follows that He is two simply and not incidentally. And this is “to dissolve Jesus” (1 John 4:3), for everything, in so far as it is, is one.”
Next - CONTRA GENTILES: BOOK FOUR: SALVATION - Chapter 39 WHAT THE CATHOLIC FAITH HOLDS ABOUT THE INCARNATION OF CHRIST