March 20, 325.
312 bishops of the newly-legalized Christian Church meet in Nicea at the behest of the Emperor of the Roman Empire himself. Their task? To determine, once and for all, what the Church believes about the nature of Christ -- was He God, Man, or both?
The conflict started because of a teacher named Arius. Arius claimed that Jesus was simply a creation of God. He was the first creature, but only a creature. Hi substance and nature were not the same as God's, and there was a time when He did not exist.
In the other corner was Bishop Alexander of Alexandria. He was appauled at the suggestion that Christ was less than God. The dispute caused conflicts all over the Empire, and Emperor Constantine wanted it stopped -- quickly.
Many of the bishops present had suffered greatly under the rule of Diocletian. They had risked their lives for the faith, and for Christ. They couldn't stand to see this man Arius make Christ into a simple man -- He was God incarnate! When a bishop rose to defend Arius, they tore the speach from his hands. The conflict threatened the unity of the Church.
After much debate and arguement (and there IS a difference between the two!), the issue was finally resolved. God and Christ were the same substance (in Greek, homoousion
). Christ was co-eternal with God. But in many ways, Nicea only started the theological ball rolling. Later councils would argue about the nature of Christ, the virgin birth, and other Christological concerns. But without the Council of Nicea, there would have been no starting point at all.