How did the First Ecumenical Council of Nicaea Change Christianity?

Learn why the first of the great Ecumenical Councils, held at Nicaea in 325 CE, was so important.

Sep 22, 2023By Cameron Hughes, MA Field Archaeology, MA Politics

first ecumenical council of nicaea

 

Prior to the proliferation of Christianity under Emperor Constantine the Great, the trials and tribulations of the Church were of little interest to wider Roman civilization. Christians had faced several persecutions from the 1st to 3rd centuries and had largely remained a fringe cult of the eastern plebs. As a result, Christian theology had not developed much past early scripture, with some forays into Gnosticism. With Constantine’s patronage, Christianity and its ecclesiastical debates became matters of importance at the first of the great Ecumenical Councils of the Church, the Council of Nicaea.

 

Before the Council of Nicaea: Trials & Tribulations of the Early Christians

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La Crucifixion, by Andrea Mantegna, 1456-1459, via The Louvre

 

Following the events of the Old Testament, church historian Eusebius (Book I, Chapter 2.23) informs us that near the dawn of the Roman Empire the human race was blessed by the presence, on earth, of God in human form. We now know that the birth of Jesus took place at some point between four and six BCE in the town of Bethlehem in the Roman client kingdom of Judaea. In Jesus’ childhood the regime of the client King Herod was weakened under his sons and the Romans more or less took responsibility for the administration of the region as a new imperial province.

 

Jesus claimed he was the son of the Abrahamic God of the Old Testament. Awaiting the Messiah, John the Baptist baptized Jesus in the River Jordan, beginning his Ministry. He then traveled the area of modern Palestine teaching the Gospels and accumulating disciples. Though many of his deeds are recorded in the New Testament, the non-Christian historian Josephus also accounts for his existence as a man who was “wise,” “virtuous,” and “good”. The historian Lactantius on the other hand tells us how in the latter days of the rule of the Emperor Tiberius, Jesus was crucified by the Roman Prefect, Pontius Pilate, for the sectarian unrest he was sowing in Roman Judaea.

 

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Mosaic of the baptism of Christ, surrounded by the 12 apostles, from the Arian Baptistry of Ravenna, 5th-6th centuries, via Wikimedia Commons

 

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Both Eusebius and Lactantius tell us of how, on the third day after his death, Jesus was resurrected. He then gathered his disciples, instructed them further in the scriptures and sent forth the 12 apostles to spread his teachings across the earth before he ascended to the heavens. The apostles traveled far and wide, spreading the teachings of Christ and founding Bishoprics in some of the largest cities in the empire, including Antioch, and Rome founded by Peter himself. As the new faith grew, so did the awareness of the imperial authorities to its existence.

 

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The Christian Martyrs’ Last Prayer, by Jean-Léon Gérôme, 1883, via Wikimedia Commons

 

The first, and most notorious, of the persecutions came under Nero after the Great Fire of Rome, in 64 CE. During this persecution Peter was martyred. Persecution was never an institutional imperial policy as the Roman government was generally tolerant of all religions. For example, the persecutions of the 3rd century under Decius, Diocletian, and Gallienus were all dependent on the incumbent emperor and were restrictive of the legal and economic rights of Christians rather than being explicitly murderous or violent. They were primarily an effort to restore the unity of belief and purpose in the Roman world after the upheavals of the 3rd century, rather than specifically in opposition to Christian ideology.

 

The Church Develops a Mind of Its Own

apotheosis council of nicaea
Apotheosis of Venice in the Palazzo Ducale, by Paolo Verenese, 1585, via Web Gallery of Art

 

As the early Church expanded throughout the ancient world it became part of a great cultural fusion. It encountered the ideas of apotheosis, the wider Graeco-Roman pantheon of deities, and the Hellenic philosophies. The latter of these influences sparked a new line of thought within Christianity that would directly lead to the necessity of the Council of Nicaea. As the Church encountered the Socratic and Platonist methods of inquiry in the pursuit of knowledge as well as the rationalism of Aristotle, debates began about the teachings and nature of Christ. The “gnostics” as they came to be known, believed that salvation could be obtained through the acquisition of knowledge of the universe and its mysteries.

 

This meant that the men of the Church began to explore and interpret the Divinity in new ways, trying to reach conclusions through logic when scripture alone could not explain. Therefore, like the philosophers of classical Greece, metaphysical debates emerged between leading members of the clergy. One of these persistent debates was to be on the nature and relationship of the Holy Trinity.

 

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The Descent of the Holy Spirit, by Anthony Van Dyck, 1618-1620, via Art Bible

 

 

In the mid-3rd century Paul of Samosata, Bishop of Antioch (an apostolic see), began teaching that although the Holy Trinity was divine, Jesus Christ was not part of that Trinity and was in fact a mortal man influenced by the Holy Spirit. This would relegate Christ to the station of a prophet, akin to Abraham, and not the son of God. Though such technicalities may seem unimportant to us, I would direct the modern reader to the emotional evocations seen today in “culture wars” and the ideological debates between left and right. For the early Christians, these issues were as, if not more, important as they related to the existence of life itself.

 

Though it was not the only doctrinal debate that resulted from the attempted interpretation of God’s nature by mortal men, Paul of Samosata is important. It is the first instance of imperial intervention in a Church dispute. Three synods were held at Antioch in the 260s which eventually condemned Paul, but he refused to vacate his seat. Eventually, an appeal (272 CE) was sent to the Emperor Aurelian (before he became unfavorable to the Christians) to remove Paul, which he did (Eusebius, Book VII, Chapter 30.19).

 

Emperor Constantine and Church Unity

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The Vision of the Cross in the Apostolic Palace of the Vatican, by the School of Raphael, 1520-1524, via Vatican Museums

 

 

Born in the same year that Aurelian was persuaded to condemn Paul of Samosata, Constantine grew up aware of the need for unity. His childhood bore witness to the final years of the Crisis of the Third Century and his formative adolescent years were spent in the upper echelons of imperial politics. His father, Constantius I, was an elemental part of Diocletian’s governmental model, the Tetrarchy, which sought to stabilize the Roman government and empire. Like Aurelian, Constantius was an adherent of the cult of Sol Invictus, a sect that believed their deity was preeminent among the Roman Gods. However, Constantius was tolerant and even sympathetic to the Christians, some of which he accommodated at his court in the west.

 

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Solidus of Constantine the Great, 326-7, via the British Museum

 

Like his father, Constantine remained open-minded to new beliefs, despite a stay at the court of the eastern Augustus, Galerius, who was an avid persecutor of the Christians.

 

Constantine eventually succeeded his father as the western Augustus, despite Galerius’ disapproval. His limits were not limited to his quarter of the empire however and between 312 and 324 CE he tore down the Diocletianic model and asserted his sole rule over the Roman world. Over this period Constantine also began to favor the Christian God for a number of beneficial reasons though he did not receive baptism until right before his death in 337 CE.

 

For Constantine, it was crucial that the whole Church was united. If it were then his propagation of the Christian faith conferred upon him the divine blessing of the one true God. This added a transcendent layer of legitimacy to his authority as the ruler of the Roman world, and to his potential dynastic successors. If the Church were to be in schism or doctrinal dispute, then he was no longer ordained by the sole Divinity but merely another patron deity akin to Sol, Elagabal, or Apollo. This, therefore, left his position as emperor open to dispute, vulnerable to usurpations and revolts.

 

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St Augustine arguing with Donatist heretics, more than a century after the original schism, by the Vergós Group, 15th century, via The Historical Christian

 

Constantine’s first major foray into the disputes of the Church came during the Donatist Schism, for which he assembled the Council of Arles, 314 CE, in southern Gaul. In short, during the Diocletianic persecutions, some of the clergy in Africa Proconsularis (as in other provinces) had cooperated with the imperial authorities, handing over their copies of scripture. As a result, hardliners in the church labeled them traditores (those who hand over) and refused to recognize their consecratory authority. Caecilian, the Bishop of Carthage was supposedly consecrated by a traditore and these hardliners, under Bishop Donatus, refused to recognize his authority.

 

Constantine, initially misunderstanding the controversy, sent money to Caecilian to try and appease those still scorned by the persecutions but this only highlighted the incumbent’s favorable position and angered the Donatists. They sent several appeals to Constantine which eventually led to the Council of Arles where the Donatists were condemned. They continued to appeal to the emperor who was clearly more concerned with Church unity than doctrinal minutiae. The Donatists remained a thorn in the emperor’s side enough to provoke him to order the violent confiscation of Donatist churches and the exile or murder of their clergy. As he came to realize his heavy-handed policies had not led to Church unity he became more moderate in his treatment of the Donatists. He now recognized that the secular authority could not enforce ecclesiastical harmony and the next dispute would have to be dealt with differently.

 

The Council of Nicaea

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Icon of Constantine and the Bishops presenting the Niceno–Constantinopolitan Creed of 381, via Wikimedia Commons

 

 

Like the earlier Gnostics and the debates of Paul of Samosata, a key issue of Christology remained the connection between God the Father and God the Son. Again, the controversy would arise in the Greek-speaking east, this time in the episcopal see of Alexandria in Egypt. Arius, a presbyter, was in disagreement with Alexander, Bishop of Alexandria, over the relationship between the Father and Son of the Trinity.

 

Though complex, the main arguments of Arianism can be summarized as follows: If God the Son was begotten by God the Father, there must have been a time, even if before creation itself, that God the Son did not exist.Therefore, God the Son is an inferior and separate deity to God the Father. Again, such details may seem insignificant to our modern sensibilities, but if such a doctrine were true it could have had disastrous consequences for the early Church.

 

Arius’s beliefs would mean that the Holy Trinity was in fact made up of two, if not three divine beings of differing status. This would also mean that Christianity itself was polytheistic and could no longer claim to worship the one true God but two or three separate Divinities instead. After having torn down the pagan temples and identified the gods of the Graeco-Roman pantheon as demons, how could the church now admit it was wrong about monotheism? Added to this, if the Church could not decide on who or what their God was, then how could they decide how best to worship Him or follow His teachings? Essentially, Arius had started a heretical ideology that could threaten the very foundations of the Christian faith.

 

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Mosaic of Christ Pantocrator (ruler of all) from the Church of the Holy Wisdom (Hagia Sophia) in Constantinople (Istanbul), 12th century, via Wikimedia Commons

 

Arianism did not linger on the fringes of Christian theology, and its teachings convinced some of the most powerful bishops in the eastern empire as well as Eusebius of Nicomedia and Eusebius of Caesarea, both associates of Emperor Constantine. However, as a laymen and the secular ruler of the empire, Constantine’s concerns were with unity rather than Christology. A synod of the bishops of Egypt and Libya sent Arius into exile, and after Constantine’s final victory over Licinius in 324 CE, he sought to restore church unity. He wrote to the concerned parties on several occasions stressing the importance of peace and reconciliation in Church affairs, but it was no use. Eventually, he recognized that to guarantee Church unity, he would need the agreement of the whole Church and so convened the Ecumenical Council of Nicaea in 325 CE.

 

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Icon from the Mégalo Metéoron Monastery in Greece, representing the First Ecumenical Council of Nikea, by Jjensen, via Wikimedia Commons

 

We are thankful, again, to Eusebius of Caesarea for an insight into the proceedings of the council from the third book of his Life of Constantine. He tells how “God’s ministers from all the churches which abounded in Europe, Libya, and Asia ” were present, including from outside the empire, from Persia and Scythia. Constantine also used this assembly to assert his primacy and importance in the affairs of the Church; only after all the bishops congregated in the great palace did he enter in procession, bidding them all to be seated after him. He addressed the attendees stressing that “intestine strife within the Church of God, is far more evil and dangerous than any kind of war.” He then seems to have acted as an adjudicator of sorts as the bishops debated the issue at hand.

 

Though many of the bishops attending were initially sympathetic to Arius, after hearing many of his teachings read allowed, they soon recognized Arianism as blasphemous. In the end a statement of faith was conceived which took a homoiousian view on the Trinity, that the Son was consubstantial (of the same substance) with the Father, i.e. equal.

 

At the council it was decided to reject the Jewish dating for the celebration of Easter, standardizing the newer Christian practice. Many of the earliest canonical laws were also created.

 

The Council of Nicaea and the Nicene Creed

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Bust believed to be Constantius II, a suspected Arian emperor and son of Constantine the Great, 4th or 5th century, via Wikimedia Commons

 

The conclusions of the first ecumenical council appeared to reconcile all but two of the approximately three hundred bishops in attendance and became known as the Nicene Creed. The two bishops, and Arius, were exiled by the emperor for their heresy, though some years later, Eusebius of Nicomedia, himself an Arian sympathiser, persuaded the emperor to take a more lenient stance on the heretics. Eusebius himself supposedly said that he only signed the Creed with his hand, not heart. Eusebius was also the priest who baptized the emperor before his death and was close to Constantine’s son and successor, Constantius II, another Arian sympathizer.

 

Ultimately, though the Nicene Creed is one of the only creeds universally accepted by (nearly) all Christians today, it did not achieve Constantine’s vision of Church unity at the time. As mentioned, his son Constantius II had Arian views and Arianism became the denomination of several other peoples such as the Goths and Vandals. However, what the Council of Nicaea did was to inextricably link the secular and ecclesiastical powers in Europe for the rest of antiquity and the Middle Ages.

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By Cameron HughesMA Field Archaeology, MA PoliticsCameron is a contributing writer with an interest in the transitional period between late antiquity and the early Middle Ages in Europe. He holds an MA in Field Archaeology from the University of York, and an MA in Politics from the University of Birmingham. His Masters dissertations have been on the end of Roman Britain and the concept of ‘crisis centuries’ in Western history.