The First Council of Nicaea, the first ecumenical (worldwide) council held by the church, is best known for its creation of the Nicene Creed, the earliest assertive statement of Christian orthodoxy. The council was convened in 325 by the Roman Emperor Constantine I in an attempt to settle the controversy which was raised by Arianism over the nature of the Trinity. It is important to note that Constantine had converted to Christianity and had “called the council together because he clearly had hoped for Christian support in holding his fragile empire together.”1 Held in Nicaea (which is now modern day Turkey), over 300 bishops and non-episcopal Christian thinkers were brought together for the event.2 The council’s major controversy was about determining whether Christ was both human and divine. “The crucial debate centered on the statement that the Son was “of the same substance” (homoousios) with the Father.”3 The predominant idea of Arianism is the unique and superior nature of the singular divine being. At the center of the controversy was a presbyter in Alexandria named Arius. His belief (centered around Proverbs 8:22 which states The Lord brought me forth as the first of his works, before his deeds of old.) was that the Son was not of the same essence as the Father, that the Son was created by the Father. From this line of thought, he argued that there would be more than one God. Therefore, the Son must be deemed a creature that has been given life from nothing and has had a beginning. Moreover, the Son can have no direct knowledge of the Father since the Son has limits and is of a different type of existence. Support for Arius from powerful bishops like Eusebius of Caesarea and Eusebius of Nicomedia further illustrate how Arius' Christology was shared by other Christians in the Empire. With all of this said, one could ask why this is important enough to debate. A good reason for the Arians to entertain such ideas would be the belief that “the divine cannot change or suffer – so how could a crucified human being be divine?”4
The two men that stood in direct opposition with these views were Alexander, the bishop of Alexandria and Athanasius, a deacon from 311 to 328, when he succeeded Alexander as bishop.5 Their belief was that Christ was both human and divine. Known to be an obstinate man, Athanasius was clearly the one to spearhead the debate against Arianism. Athanasius held steadfast to the idea that the Son was begotten eternally. As the Arians maintained their argument, Athanasius pointed out that anything created is made of completely different matter. He thought that being “begotten” made Christ divine and not a creature and therefore “of the same substance” as the Father.6 Athanasius argued that if the Arian position were true, then we would be of the same nature as Christ. “He would be liable to change and variation,”7 meaning he would be as susceptible as we are to the temptations of evil and therefore, our deliverance could not be assured. As both sides of the issue had gained significant support with no apparent end in sight, Emperor Constantine ordered the discussions of the council to commence in June 325. The council decided to vote against the Arians so overwhelmingly that only two bishops in attendance refused to sign the creed.8 These 2 bishops (Theonas and Secundus, both from Egypt) were banished.9 Constantine condemned Arius and “on June 19, 325, the Nicene Creed affirmed that the Son shared the Father’s divine nature.”10 The emperor then exiled Arius, an act that, while establishing unity of church and state, stressed the significance of secular support in matters relating to the church. Of course, the outcome of this huge moment in the course of mankind is well known to everyone. But think about this possibility: what if Arianism had prevailed? Would Christianity have been reduced to the ranks of fairytales or folklore? There is an existing example of Arianism alive in the world today found in the Jehovah’s Witnesses. Their views on the Trinity (“The Trinity teaching is a deviation from the truth, an apostatizing from it”11) demonstrate that "the Christology of Jehovah’s Witnesses, also, is a form of Arianism; they regard Arius as a forerunner of Charles Taze Russell, the founder of their movement.”12
While the First Ecumenical Council of Nicaea did not initiate the beginning thoughts concerning the nature of the Trinity, it should go without saying that it had huge implications in the development of Christology (“the study of the Person of Christ, particularly the union in Him of the divine and human natures, and of His significance for Christian faith”13). Without the findings of the council, the ideals that found the basis for Christology could have very easily never been known. For present-day Christians who are committed to maintaining and preserving orthodox Christian beliefs, we often need to go back to the historical orthodox doctrine of Christology. The discussions and important historical doctrines concerning Christology help us to set limitations from historical comprehension. The Council of Nicaea was historically significant because it was the first effort to reach an agreement in the church through an assembly representing all of Christendom.