On May 20, 325 A.D., the Roman Emperor Constantine opened the First Council of Nicaea. The first ecumenical council of the Christian Church, the meeting addressed several key topics among early Christians, including the divisive issue of Arian Christianity.
Throughout the second and third centuries A.D., the Christian Church had been spreading steadily within the Roman Empire. There are several reasons why Romans turned to Christianity at this time. Roman culture and society had always been highly class conscious, and Christianity offered an equality that perhaps had never existed before in Rome. All men and women were brothers and sisters before Christ, regardless of social class. Indeed, the early church counted many women among its ranks of organizers and proselytizers.
Christianity also placed an emphasis upon charity, and Christian bishops often helped the poor and less fortunate in a way that seemed difficult for many Romans to comprehend. Of course, one cannot discount faith. Christ offered victory over death, something that the traditional Roman pagan religion, which worshiped the pantheon of Jupiter, Venus and others, never firmly promised.
The Christians of Rome suffered periods of persecution within the empire, the first under the reign of Nero in 64 A.D. when they were blamed for the great fire. Later persecutions either sprang up in various localities or were directed by the state. Romans resented that the Christians would not sacrifice to the traditional gods, particularly when as a form of military service. Also, many misunderstandings plagued relations between Christians and non-Christians. Many Romans believed that when Christians talked of eating the flesh and drinking the blood of Christ, they were practicing some form of cannibalism. The Christian practice of calling fellow churchgoers, even spouses, as “brother” and “sister” was interpreted as some form of incest.
A Roman general and religious pagan traditionalist, Constantine fought his civil war to win the imperial throne. Shortly before the Battle of the Milvian Bridge in 312 A.D., however, Constantine said that he had a vision in which he saw a cross and heard the words, “In this sign, you shall conquer.” Constantine won the battle and soon installed himself in Rome as emperor. He became a champion of Christian rights, though he himself would not be baptized until shortly before his death in 337 A.D. Under Constantine, the Christian Church, which had been at many times an underground organization, flourished and quickly became a major force within the empire.
The Christian Church was not a monolithic institution, however. Various factions and practices had taken root over the years, and Constantine saw the need for a unity of doctrine and a clearer organization for the church's hierarchy. There was also a critical issue that had already caused many problems within the church and threatened serious discord: the spread of Arianism.
In his book “Lost to the West: The Forgotten Byzantine Empire That Rescued Western Civilization,” historian Lars Brownworth wrote: “Just as the empire came together politically, however, a new and deadly heresy threatened to permanently rip it apart. It started in Egypt when a young priest named Arius started teaching that Christ was not fully divine and was therefore inferior to God the Father. Such a teaching struck at the heart of the Christian faith, denying its main tenet, which held that Christ was the incarnate word of God, but Arius was a brilliant speaker, and people began to flock to hear him speak. The church was caught completely off guard and threatened to splinter into fragments.”
With only sporadic, almost cell-like leadership throughout the empire, the traditionalist Christians could not rally to oppose the spread of Arius' teachings, and many began to follow his form of worship. Many scholars believe that Constantine himself took no formal position on the Arian heresy, he simply wanted unity and was willing to back whichever side looked best able to reach that end. A council of bishops was needed to formally decide this and other matters.