By excluding several extreme positions from the circle of orthodoxy, the formulation of the doctrine of the Trinity in the 4th century determined the course of subsequent discussion about the person of Christ. It also provided the terminology for that discussion, since 5th-century theologians were able to describe the relation between the divine and the human Christ by analogy to the relation between the Father and the Son in the Trinity. The term that was found to express that relation in Christ was physis, “nature.” There were three divine persons in one divine essence; such was the outcome of the controversies in the 4th century. But there were also two natures, one of them divine and the other human, in the one person Jesus Christ. Over the relation between those two natures the theologians of the 5th century carried on their controversy.
The abstract questions with which they sometimes dealt in that controversy, some of them almost unintelligible to a modern mind, must not be permitted to obscure the fact that a basic issue of the Christian faith was at stake: How can Jesus Christ be said to partake of both identity with God and fellowship with humanity? The parties
During the half century after the Council of Constantinople, several major points of emphasis developed in the doctrine of the person of Christ. Characteristically, these are usually defined by the episcopal see that espoused them. There was a way of talking about Christ that was characteristic of the see at Alexandria. It stressed the divine character of all that Jesus Christ had been and done, but its enemies accused it of absorbing the humanity of Christ in his divinity. The mode of thought and language employed at Antioch, on the other hand, emphasized the true humanity of Christ, but its opponents maintained that in so doing it had split Christ into two persons, each of whom maintained his individual selfhood while they acted in concert with each other. Western theology was not as abstract as either of those alternatives. Its central emphasis was a practical concern for human salvation and for as irenic a settlement of the conflict as was possible without sacrificing that concern. Even more than in the 4th century, considerations of imperial politics were always involved in conciliar actions, together with the fear in countries like Egypt that Constantinople might come to dominate them. Thus, a decision regarding the relation between the divine and the human in Christ could be simultaneously a decision regarding the political situation. Nevertheless, the settlements at which the councils of the 5th century arrived may be and are regarded as normative in the church long after their political setting has disappeared.
The conflict between Alexandria and Antioch came to a head when Nestorius, taking exception to the use of the title “Mother of God” or, more literally, “God-Bearer” (Theotokos) for the Virgin Mary, insisted that she was only “Christ-Bearer.” In that insistence, the Antiochian emphasis upon the distinction between the two natures in Christ made itself heard throughout the church. The Alexandrian theologians responded by charging that Nestorius was dividing the person of Christ, which they represented as so completely united that, in the famous phrase of Cyril, there was “one nature of the Logos which became incarnate.” By that he meant that there was only one nature, the divine, before the Incarnation but that after the Incarnation there were two natures indissolubly joined in one person; Christ’s human nature had never had an independent existence. There were times when Cyril appeared to be saying that there was “one nature of the incarnate Logos” even after the Incarnation, but his most-precise formulations avoided that language.
The Council of Ephesus in 431 was one in a series of gatherings called to settle this conflict, some by one party and some by the other. The actual settlement was not accomplished, however, until the Council of Chalcedon was convened in 451. The settlement at Chalcedon
The basis of the settlement at Chalcedon was the Western understanding of the two natures in Christ, as formulated in the Tome of Pope Leo I of Rome. Chalcedon declared:
We all unanimously teach…one and the same Son, our Lord Jesus Christ, perfect in deity and perfect in humanity…in two natures, without being mixed, transmuted, divided, or separated. The distinction between the natures is by no means done away with through the union, but rather the identity of each nature is preserved and concurs into one person and being.
In that formula the valid emphases of both Alexandria and Antioch came to expression; both the unity of the person and the distinctness of the natures were affirmed. Therefore, the decision of the Council of Chalcedon has been the basic statement of the doctrine of the person of Christ for most of the church ever since. The Western church went on to give further attention to the doctrine of the work of Christ. In the Eastern church the Alexandrians and the Antiochians continued the controversies that had preceded Chalcedon, but they clashed now over the question of how to interpret Chalcedon. The controversy was an effort to clarify the interpretation of Chalcedon, with the result that the extremes of the Alexandrian position were condemned just as the Nestorian extreme of the Antiochian had been. The Alexandrian position was known in the Western church as the heresy of monophysitism, or the teaching that Jesus had only a divine nature, until the 20th century.
Emerging from all that theological discussion was an interpretation of the person of Christ that affirmed both his oneness with God and his oneness with humanity while still maintaining the oneness of his person. Interestingly, the liturgies of the church had maintained that interpretation at a time when the theologians of the church were still struggling for clarity, and the final solution was a scientifically precise restatement of what had been present germinally in the liturgical piety of the church. In the formula of Chalcedon that solution finally found the framework of concepts and of vocabulary that it needed to become intellectually consistent. In one sense, therefore, what Chalcedon formulated was what Christians had been believing from the beginning, but, in another sense, it represented a development from the earlier stages of Christian thought. The interpretation of Christ in Western faith and thought
With the determination of the orthodox teaching of the church regarding the person of Christ, it still remained necessary to clarify the doctrine of the work of Christ. Although it had been principally in the East that the discussion of the former question was carried on—though with important additions from the West—it was the Western church that provided the most-detailed answers to the question, Granted that this is what Jesus Christ was, how are we to describe what it is that he did? Doctrines of the person and work of Christ The medieval development