Chi rho — with the “ch” in chi pronounced as it is in “Bach” — are the Greek letters that have served as the sign for “Christ” since the early years of Christianity. They are the first two letters in the Greek “Christos,” and they look like an English x and p, respectively. But who or what is the entity the Chi Rho stands for? Christian understanding of Christ’s nature has never been a straightforward road — nor should we expect it to have been, given the depth of the issues that become apparent as soon as one looks even a little closely.
The area of theology that deals with the nature of Christ is called Christology, and the christological disagreements (some more major than others) that existed right from the inception of Christianity are so numerous that it is impossible to raise them all here. The primary disagreements surrounded the question of whether Christ was fully God incarnate with only the outward appearance of humanity; whether he was God incarnate with both true divine and true human natures in the same body; or whether he was a subordinate, semi-human semi-deity whom God created and endowed with special attributes. It fell to two main Ecumenical Councils to hash out these questions: first Nicea and then, to address further christological questions that followed from the Nicean decision, Chalcedon.
In the year 325 Emperor Constantine, the first emperor to convert to Christianity, wearied of all the arguing and called the Council of Nicea to work it all out, hoping that everyone would then quiet down and be satisfied. The council, drawing on years of theological work, determined that Christ was of “same substance” (homoousios) with the Creator, rather than “like substance” (homoiousios). Both views had many advocates, and these advocates themselves differed with respect to the details of Christ’s nature, and how Christ would thus relate to the Creator. The strongest defender of the Nicean “one substance” view at that time was Athanasius, while the strongest proponent for the “like substance” view was Arius.
Though it may sound trivial and overly speculative to the point of meaninglessness, the “substance” debate gets to the heart of the identity of the Creator and the role of Christ, which in turn is a matter at the heart of Christianity. The “high Christology” of John’s Gospel contributed to the co-identification of Christ’s nature with the Creator, particularly John 1 with its statement that all things were created through the Word (Logos: reason, word, logic) that then came down and became flesh among us in Christ. Other statements in John that are attributed to Christ, such as “I and the Father are one,” also contributed to the Nicean understanding. Other words and actions of Christ, however, particularly in the other Gospels, give a strong impression of Christ’s true humanity: Jesus prays to God, gets hungry and thirsty, weeps, feels physical pain, and experiences the desire to be alone and to remove himself for a time from the throngs. These facts contributed to the Arian view that Christ was not of one nature with the Creator but rather a subordinate, created being who at some point became endowed by God with suprahuman characteristics and purposes. In the Arian view, Christ did not eternally exist with God before time; in the Nicean view, since Christ is a same-substance manifestation of God (a hypostasis), he did eternally exist with God before time.
The attraction of the Arian view is immediately apparent. It contains no paradoxes and no mind-bending issues involving the relationship between God and Christ as co-equal Persons sharing one substance. (And this is not even to raise the matter of the Holy Spirit as the third Person of the Trinity!). The Arian view at first glance is simpler and more common-sense to us. And it certainly resolves the question of how Jesus could have been praying to God if he had any divine nature. But it does not take into account major statements in John’s Gospel, such as those mentioned above. Now from a strict historian’s perspective, this is no problem at all: the different portrayals of Christ simply illustrate different understandings of Christ among early Christians who wrote the New Testament. This is well and good and no doubt accurate. But from the perspective of a Christian theologian or laity, how these different portrayals coalesce to form an overarching image of Christ matters a great deal. To the theologian or laity, the ultimate nature of who Christ was or is becomes a central matter. The New Testament portrayals of Christ are the basic documents such a person has to construct his or her own answer to the question: “Who was this man?”
Where the Arian view runs into real difficulty is the question of human salvation through redemption from sin and the consequent assurance of eternal life. The Gospels and many epistles in the New Testament (from Paul and otherwise) identify these things as wrapped up in Christ’s purpose on Earth, to one or another degree of emphasis depending on the text. How is Christ’s birth, suffering, death, and resurrection redemptive or salvific on a global and eternal scale if he is only human? Or even if he is semi-divine, adopted in some special way by God to perform an extraordinary purpose? How is his life redemptive and salvific for the human species for all time if he is anything less than fully divine? No entity, it was argued, who is not God could accomplish — could have the right to accomplish — such a feat. When followed through to its end, the Arian view seemed to raise more problems and inconsistencies than it solved. So Nicea determined that Christ was of one substance with God: he became fully incarnate as a human, but he was the Word, the Logos, who from the beginning was begotten from the Creator and not made.
But christological analysis did not end at Nicea. After that council, people continued to examine the further consequences of the Nicean decision. If Christ was of one nature with the Creator, how could he have been praying to that Creator in the Gospels? Would he not then have been praying to himself? If he was of one nature with the Creator, how did he appear genuinely to feel most of the things that humans feel, both physically and emotionally? The danger of glossing over these human traits became apparent as an unintended consequence of Nicea. A school of thought gained strength in Antioch that did not deny Christ’s divine nature, but most emphasized his human nature and the importance of clearly distinguishing the two Persons, the Creator and the Christ, even if one allowed that they shared the same substance. The Antiochene school sought to avert any simple blurring of the Christ and the Creator that failed to note any distinction between the two. On the other hand, Alexandria, a competing theological center, produced some theologians who emphasized Christ’s divine nature almost at the expense of his human one (sometimes inadvertently so). A growing group that came to be known as Monophysites (from “one nature/body”) asserted that Christ had only one true nature — that of God. At most, the divine Logos took up residence in Jesus’ human flesh, but the two were not inherently connected or inseparable in the person of Jesus.
The Council of Chalcedon of 451 was convened to form a definitive position on these christological issues, and to answer the Monophysite contention that Christ had only one nature. Chalcedon re-affirmed Nicea but went further in detail, asserting that Christ indeed had two natures, one divine and one human, and that each of these natures was “full.” That is, neither the divine nor the human nature in Christ was adulterated or incomplete; both cohered together in his Person. The natures were not commingled — Christ was not some divine-human hybrid or demigod. Each nature existed in itself, full on its own, not watered down — yet in his Person completely inseparable, indivisible, inextricable. Christ would not be Christ without the divine nature, and Christ would not be Christ without the human nature. Thus the Second Person of the Trinity became Jesus Christ at the incarnation, within a woman of ordinary rank, in a tiny and powerless country that had been subsumed into the Roman Empire. Before this incarnation, the same Word was still the Second Person of the Trinity, and had eternally been so.
The Nicean and Chalcedonian formulations allow both for the necessity of Christ’s fully divine nature in his redemptive activity, and for his clearly human traits. The christology put forth by these councils contended that in one man dwelt God-nature and human-nature each full in itself, yet in that man inseparable from one another. This, it was determined, is the entity behind the Chi Rho.
What does all this matter to a Christian going about his or her life, trying to live by Christ’s admonishment that the two greatest Commandments are to love God and love your neighbor? Perhaps, not much. Certainly, not every Christian embraces the christology of Nicea and Chalcedon. But perhaps, we could take more seriously the divine mandate to honor, respect, and love one another if we saw in our own species the potential that our Creator has always seen.
© Elizabeth Keck 2010
* For a comprehensive but clearly-written overview of the major developments in historical theology, I recommend to interested readers A Short History of Christian Doctrine by Bernhard Lohse, translated by F. Ernest Stoeffler.