COMMUNICATION OF LANGUAGES. - The term "i." which, according to its etymology, means property and in vulgar usage means native tongue, philosophically indicates an attribute proper to a nature. The expression "c. of i." is then used by theologians in Christology to designate the mutual predication of the human and divine attributes in Jesus Christ. The c. of i. follows as a logical consequence from the fact that in Christ the divine and human natures are united; indeed, it is nothing but the translation onto the logical plane of that communication or ontological union existing in Christ between the human and divine natures and therefore between the attributes of the one and the other nature.
It is therefore easily understood, and the history of the dogma confirms it, that, if on the one hand the c. of i., understood in a vague and indeterminate sense, is necessarily admitted by all those who recognize in Christ the character of God-Man, a more precise and exact interpretation of it is bound up with the way of conceiving the unity of Christ and the relations in him between the divine and human natures.
Nestorianism (v.), which divided Christ into two persons accidentally united, admitted the c. of i. only in the sense that the predicates of one person can be attributed to the other by a moral attribution, just as, in general, the dignity, authority and honor of a father can be morally referred to his children.
In a completely opposite direction moved Monophysitism (v. MONOFISITI), which, fusing the two natures into one, pushed the c. of i. to the point of attributing to one nature the properties of the other.
Holding a middle way between these two interpretations, of which the first errs by defect and the second by excess, Catholic doctrine specifies the meaning of the c. of i. in the following way:
1) Human attributes can be predicated of the subject Christ, denominated according to the divine nature, as in the propositions: the Word of God, the Son of God, was born in time, had a mother, suffered, died; and vice versa, divine attributes can be predicated of Christ denominated according to the human nature, e.g.: Christ as man, the son of the Virgin Mary, the son of man, is creator of the universe, is begotten in eternity by the Father, is with the Father the principle of the Holy Spirit. In fact, the hypostatic union entails that Christ is a single "I," a single person having two natures; therefore, propositions such as those cited above are true, in which identity is established between the person having the properties of one nature and the person having the properties of the other nature.
2) On the other hand, however, the dogma of the hypostatic union (v.) entails that the two natures remain in Christ distinct and unconfused; whence it follows that they cannot mutually predicate one another, nor can the properties of one be predicated of the other. It would be a grave error to affirm that the human nature of Christ is omnipotent, eternal, omniscient; or that the divine nature of Christ is passible, mortal. One would fall into the same error by affirming that Christ, insofar as he is man, is eternal, or that Christ, insofar as he is God, died; for these restrictions "insofar as he is man," or "insofar as he is God," have the value of indicating in the nature of man or of God the reason for the predicate, and therefore such propositions amount to affirming that one nature possesses the properties of the other, thus falling into Monophysitism.
In conclusion, according to the correct sense fixed by Catholic doctrine, the mutual attribution of the human and divine properties in Jesus Christ does not occur directly between the human nature and the divine nature, but rather between the person denominated according to one nature and the properties of the other nature.
The fact of the c. of i. is already found openly in Sacred Scripture, as, for example, in the following passages: "And the Word was made flesh and dwelt among us" (Jn. 1:14); "the Son of God is made of the seed of David according to the flesh" (Rom. 1:3); "Of whom (the Jews) is Christ according to the flesh, who is over all things, God blessed for ever" (Rom. 9:5); "Who (Jesus Christ), being in the form of God... emptied himself, taking the form of a servant... he humbled himself, becoming obedient unto death, even to the death of the cross" (Phil. 2:6-7).
The doctrine of the c. of i. was solemnly defined by the Church in the Councils of Ephesus and the Lateran (Denz-U, 116, 124, 255). The Fathers, such as Origen, Cyril of Jerusalem, Cyril of Alexandria, St. John Damascene, developed it in the polemic against the Christological heresies; and the Scholastics expressed it in philosophical formulas, precisely fixing the laws that must govern our way of speaking about Christ, among which we may recall the most important, the one concerning concrete and abstract names.
In the philosophical sense, concrete names are understood as those that designate a subject having a nature or a property of it, e.g.: mortal man, corporeal; "man" means precisely "a subject having human nature." Abstract names, on the other hand, indicate only a part but prescinding from the concrete subject in which they are destined to be realized, e.g.: humanity, rationality, mortality, body, soul. Now, the Scholastic rule affirms that the human nature and its properties can be attributed to Christ-the Word when they are expressed by concrete names, but not when they are expressed by abstract names. It is correct to say that the Word of God is corporeal, is mortal; false, on the other hand, to affirm that the Word is corporeity, is mortality, is a body. This rule finds its justification in the light of the dogma of the hypostatic union, according to which the human nature with its attributes and its parts is possessed by the Word, but is not the Word; therefore, the Word is a person who possesses the human nature, but is not the human nature and still less its parts and properties.
When dealing, however, with divine attributes, it is legitimate to predicate them of the person Christ-Man, even if they are expressed in an abstract way; e.g.: The son of the Virgin Mary is the Divinity; is the Way, the Truth and the Life. The reason for the exception lies in the fact that all divine perfections are subsistent, are themselves the substantial subject, and therefore the names that express the divine perfections can be taken as concrete names.
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Antonio Gaboardi
IDIORRHYTHMIA: EASTERN MONASTICISM.