The Council of Nicaea was both an odd and foundationally critical point in the life of Christianity. For nearly three centuries, Christians had been a despised and persecuted group among both Jews and Gentiles. Jews (those holding to the “traditions of their fathers” [Matt. 15:1-9]) hated Christians for the same reason they hated Jesus Christ Himself, namely for claiming deity for the God-man and ascribing the title of ‘Messiah’ to Jesus of Nazareth. Gentiles, particularly Romans, hated the Christians for their apparent exclusivity in religious beliefs. Romans had a pantheon of gods, but Christians would only acknowledge the singular and triune God of Christianity. In spite of this deep hatred and long-lasting persecution, the Roman emperor Constantine reversed these categories entirely. Before the battle that won him the status of co-emperor (The Battle of Milvian Bridge in 312A.D.), Constantine later claimed to have seen a vision of a ‘cross’ in the sky with the words “In this sign, conquer.” After he won his new title, Constantine – in agreement with his co-emperor from the east, Licinius – issued a decree legalizing Christianity throughout the empire. 
This was only the beginning of Constantine’s contributions to the Christian Faith, but the oddity of the first ecumenical or universal council was largely due to the mixing of the Church with the state. Constantine may or may not have been a genuine convert to Christianity, but he certainly had no biblical basis for officiating a theological debate among Church elders. Nevertheless, Constantine brought such theological debate to the most prestigious stage known to mankind – the emperor’s court. Christianity would be marked indefinitely by the political shift and, more importantly, the theological convictions of those men who gathered at the Council of Nicaea.
A large number (about 300) of bishops and presbyters gathered at Nicaea, and many were no doubt bearing the scars of persecution in their recent past, but the two most noteworthy and polarizing men were Athanasius and Arius. Arius (ca. 250 – ca. 336) was a “presbyter from Alexandria in Egypt on the North African coast.” His Christology was representative of one side of the arguments to be heard at Nicaea. While his teaching survives only in scattered pieces and in references from the texts of his antagonists, Arius stated his view of God by saying, “We acknowledge one God, Who is along ingenerate, alone eternal, alone without beginning, alone true, alone possessing immortality, alone wise, alone good, alone sovereign, alone judge of all, etc.” In logical succession, Arius formulated a syllogism for his view of Christ. “If the Father begat the Son, he that was begotten had a beginning of existence; hence it is clear that there was when the Son was not.” Noll continues by saying, “English translation of this syllogism is difficult, for Arius was careful not to say, ‘there was a time when the Son was not,’ since Arius conceded that the Son had been begotten before time began.”
Arius’ view was clearly a denial of the eternal deity of Jesus Christ, for if there was when Christ was not, then Christ was brought into being or created at some point. This was an extreme heterodox view among Church leaders, including those in Alexandria. Alexander, the bishop of Alexandria was accused (by Arius) of being a Sabellian because of his view of the unity of God the Father and God the Son. Sabellians were a type of Monarchianist, which were called such for their high view of the unity of God. Sabellians (named after the third century Roman teacher, Sabellius) understood God, single in being and in person, to have merely operated in different modes throughout human history rather than actually having manifested Himself in distinct persons. The Sabellians have also been named as ‘modalists’ or (in our contemporary contexts) ‘oneness’ theologians. Alexander was not a Sabellian, but Arius seemed unwilling or unable to see a third option.
Also in the group of Monarchianists were those called ‘adoptionists’ for their belief that Jesus was particularly adopted by God and at some point infused with the fullness of deity. However, they denied that Jesus possessed such attributes intrinsically or eternally. Both of these Monarchianist sects (Sabellians and adoptionists) were out of line from the biblical revelation, and the Church would not embrace either of them.
Origen (ca. 185 – ca. 245) was another Alexandrian theologian who sought to articulate a biblically sound understanding of the revelation of God’s ontological unity and personal distinctions. Being a speculative philosopher, he “held that Jesus was ‘generated’ from the Father, but also that this generation was ‘eternal.’” While Origen seems to have kept a strain on the paradoxical balance of generation and eternality, Arius appears to have tried to release the tension and declare a less puzzling statement of Christology – as well as Theology proper. It is important to note, as Hardy does:
“None of these positions was formally excluded by the Church’s ‘rule of faith’ as it existed in the third century, in various local forms of creeds taught to catechumens in preparation for their baptism in the threefold name. The Old Roman Symbol, known to us in later form as the Apostle’s Creed, in an excellent case in point. In the late second century converts at Rome were asked in the baptismal rite, ‘Do you believe in God the Father Almighty?’ and ‘Do you believe in Christ Jesus, the Son of God…?’ By the end of the third century the second phrase probably read as we now know it, ‘his only Son our Lord,’ thus excluding any tendency to reduce Jesus to the rank of one among many. By general agreement the Church seems thus to have rejected the extreme positions that had been explored by some Christian teachers at Rome – modalism on the one hand, and the treatment of Jesus as a mere man on the other.”
Before the Council of Nicaea, while there was indeed some glad and wide acceptance of simple affirmations about Christ – both His deity and humanity, there was no widely held clarifying statement of Christian doctrine that would provide both precision and elucidation; and this would be the platform upon which Arius would do battle with Athanasius.
Athanasius (ca. 296 – 373) was a young (about 50 years younger than Arius) assistant to the bishop of Alexandria, Alexander, and he would become the strong defender of biblical Christology for decades to come. Athanasius did not think of Arius’ arguments as mere philosophical inquiry and intellectual debate, instead he saw Arius’ position as a direct assault on the Gospel of Jesus Christ. In his treatise Of the Incarnation, Athanasius summarized the case he continued to make for the rest of his life: “If Christ were not truly God, then he could not bestow life upon the repentant and free them from sin and death.” Athanasius’ Christology was (arguably before the Council of Nicaea, but certainly after it) the central theme of Alexandrian Christology, and his work On the Incarnation “is one of those great books which develop one great theme supremely.” Athanasius saw Christology as inseparable from Soteriology; as Hardy puts it, “[Christ’s] divinity makes his life mighty and his humanity makes it ours.”
At the Council of Nicaea both Alexander and Athanasius saw fit to use precise language to articulate the biblical truth of God as revealed in one being and distinct persons. The Greek word they employed was homoousios – meaning literally “same substance.” Their point was that Jesus Christ was of the same substance as the Father, while maintaining distinction in personhood. The Nicene Creed includes the very language when it says, “…God from God, light from light, true God from true God, begotten not made, consubstantial with the Father… (emphasis added)” Emperor Constantine admired the term, for whatever reason, and the position articulated by Alexander and Athanasius was embraced as orthodox Christian doctrine. Constantine ordered that all bishops sign the creedal statement or receive the punishment of excommunication. Arius, along with some of his staunch followers, was excommunicated for his refusal to sign the document. There were some, however, that acquiesced to the creed for the moment but later wanted to insert a single letter into the precise term (homoousios) that would shift its meaning from “same” to “similar” substance. These rebellious bishops notwithstanding, Christ’s Church had won the day and Athanasius had defended her well.
At any rate, this first ecumenical council was a massive pivot point for Church history, both in the area of theological disputes and in political involvement. “Nicaea bequeathed a dual legacy – of sharpened fidelity to the great and saving truths of revelation, and also of increasing intermingling of church and world.” The Church had irrevocably swung from being totally separate from anything having to do with the state to being fully endorsed and intermingled with it. Noll says, “Nicaea was a turning point that set Christianity on a course that it has only begun to relinquish, and that only reluctantly, over the past two or three centuries. That course was the addition of concerns for worldly power to its birthright concern for the worship of God.”
The Church of Jesus Christ is indeed commissioned by Christ Himself to be of great concern for the worship of the one true God and the diligent discipleship of as many sinners as will trust Him to save. This commission may or may not have anything to do with state involvement, but since the Council of Nicaea the governmental involvement in the Church and the Church’s involvement in the political government has been a mingled mess. In our own day, in the United States of America, there is hardly a bible study or fellowship gathering that does not confuse state affairs with Church affairs – as though the success of Christ’s Church is wholly dependent upon the success of a local or national political group.
Theologically speaking, Nicaea was a bulwark of orthodox Christian doctrine. While there had been regional and local debates with their resolutions for the purity and unity of the Christian Faith, Nicaea was a flag in the ground of the universal Faith of all Christians. In our day of endless denominational differences, often amounting to little in the way of actual theological dispute, it is refreshing to remember that there is one faith and one Lord for all true Christians. May God grant us such unity, articulated in both precision and clarity, in matters of essential doctrine.
Hardy, Edward Rochie. Christology of the Later Fathers. Library of Christian Classics. Philadelphia: Westminster Press, 1954. doi:WorldCat database.
Noll, Mark A. Turning Points: Decisive Moments in the History of Christianity. 3rd ed. Grand Rapids, MI: Baker Academic, 2012. doi:WorldCat database.
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