Note 67, page 208-210: Having thus avoided making the Godhead of Christ the seat of His human weakness, Apollinarius was at once confronted by a second objection, from the side of his opponents at Antioch. His insistence upon the need for a real union, and his use of words like “mixture” and “combination” to express it, laid him open to the charge, later deservedly brought against the Monophysites, of confusing together human and divine. In his book against Diodore he draws express attention to this criticism, quoting what may well be an actual saying of his opponent: The union of God to the flesh was an event remarkable, wondrous, unique, never to be repeated. You and the predecessors who led you to this impious and unchristian misbelief do not in the least recognise this. You make a mock of the perfect union and say ‘If there be a union, the attributes of God and the attributes of the flesh no longer remain distinct’; and you urge that the perfect union is dissolved if we confess a perfect union according to the flesh which is David’s seed.” Such an argument is unjust as against the kenotic theory; for nothing it is suggested a confusion, except the injudicious language which compared the self-limited Christ to other intermediates, the mule, the colour grey, and the season of spring, and spoke of Him as neither man only nor God only but a mixture between them. But it was very necessary for Apollinarius to make the point more clear; and to do so he had only to turn the kenotic theory round and show that what was from the one side a process of self-emptying was, from the other, a transference of the human attributes to the Godhead. His great definition, “Incarnation is self-emptying,” implies his response to the Antiochenes. Christ’s limitation consists in the assumption of the conditions of human existence. Christ incarnate takes up manhood into God: the flesh by union in Christ receives the qualities of deity. The whole is explained when it is realised that the kenosis is the union, and the union is Communicatio Idiomatum [exchange of properties]. The two terms are only complementary descriptions of the single fact that in the one Christ God and man are one.
His statement of the argument can be seen most clearly in the fragments of the Contra Diodorum, and was evidently a constituent part of his Christology from the beginning. He first justifies his use of mixture by a vigorous affirmation of the entire distinctness of the body and the Godhead, in the course of which he quotes Origen’s illustration of the red-hot iron: “If the combination of iron (with fire) makes the iron itself look like fire and enables it to work the works of fire and yet does not change its nature, so the union of God to the body causes no change in the body, although the body offers to those who can touch it the energy of the Godhead.” Such a saying ought to acquit Apollinarius of the monstrous insinuation of his ancient and modern opponents that he taught the consubstantiality of the flesh and the Godhead; and in the same book he supports it by a series of arguments in which he uses the union of the soul and body wherein there is no confusion in spite of their common origin__“the commingling does not make the soul visible, nor change it into the other qualities of the body so that it can be pierced or mutilated”__to prove that a fortiori there will be no confusion between the Godhead and body which are not of common origin. This is, however, only by way of safeguard. The doctrine of transference is summed up in a single sentence which is a definite reply to Diodore’s accusation, “if the body of the Lord has become one with the Lord, the attributes of the body have His attributes on account of the body”; and this is expanded in the same book, “The properties of God and the body are united in Him: He is eternally Creator, object of worship, Wisdom, Power; these He derives from His Godhead: Son of Mary, born in this last time, a worshipper of God, progressing in wisdom, growing stronger in power; these from His body.” In one person the two series and qualities are fully and perfectly united, so that Apollinarius in the exposition of his teaching to Dionysius can summarise it in the words: “We maintain both of these, that the whole from heaven because of the Godhead, and the whole from a woman because of the flesh: we recognise no distinction in the one person, nor do we divide the earthly from the heavenly, nor do we divide the heavenly from the earthly: such division is impious.” In view of the subsequent history perhaps the most interesting of the results follow from the use of this principle of transference is the bestowal upon the Blessed Virgin of the title θεοτόκος or Mother of God. In the confession of faith called the De Fide et Incarnatione Apollinarius and his synod protest that neither they nor any sane person speak of the flesh as consubstantial with God in itself, but only as indivisibly united with the Logos to form “one person, one hypostasis, wholly man, wholly God,” and urge that in consequence of this inseparable union not of any divinity if the body apart from such union the Virgin is θεοτόκος and that if this belief in the reality and results of the union is rejected “she will no be believed to be θεοτόκος which would be an injustice and impiety foreign to every reverent soul”__words which, when taken in connection with the special allusions of Theodore to the subject, intimate that the title had already become the topic of party strife.