From what has been set down above it is clear that according to the tradition of the Catholic faith we must say that in Christ there is a perfect divine nature and a perfect human nature, constituted by a rational soul and human flesh; and that these two natures are united in Christ not by indwelling only, nor in an accidental mode, as a man is united to his garments, nor in a personal relation and property only, but in one hypostasis and one supposit. Only in this way can we save what the Scriptures hand on about the Incarnation. Since, then, sacred Scripture without distinction attributes the things of God to that man, and the things of that man to God (as is plain from the foregoing), He of whom each class is said must be one and the same.
 But opposites cannot be said truly of the same thing in the same way: the divine and human things said of Christ are, of course, in opposition, suffering and incapable of suffering, for example, or dead and immortal, and the remainder of this kind; therefore, it is necessarily in different ways that the divine and the human are predicated of Christ. So, then, with respect to the “about which” each class is predicated no distinction must be made, but unity is discovered. But with respect to what is predicated, a distinction must be made. Natural properties, of course, are predicated of everything according to its nature; thus to be home downward is predicated of this stone consequently on its nature as heavy. Since, then, there are different ways of predicating things human and divine of Christ one must say there are in Christ two natures neither confused nor mixed. But that about which one predicates natural properties consequently on the proper nature pertaining to the genus of substance is the hypostasis and supposit of that nature. Since, then, that is not distinct and is one about which one predicates things divine and human concerning Christ, one must say that Christ is one hypostasis and one supposit of a human and a divine nature. For thus truly and properly will things divine be predicated of that man in accord with the fact that the man bears the supposit not only of the human but of the divine nature; conversely, one predicates things human of God’s Word in that He is the supposit of the human nature.
 It is clear also from this that, although the Son is incarnate, neither the Father nor the Holy Spirit, for all that, need be incarnate, since the Incarnation did not take Place by a union in the nature in which the three divine Persons are tog. ether, but in hypostasis or supposit, wherein the three Persons are distinguished. And thus, as in the Trinity there is a plurality of Persons subsisting in one nature, so in the mystery of the Incarnation there is one Person subsisting in a plurality of natures.
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