If Antioch tended to emphasise the humanity of Christ, with the risk of underplaying the humanity, the other great centre of Christian thought at this period, Alexandria, supplied a remedy, although with a risk of downplaying the humanity.
The finest theologian of the early Church, Origen (c.185-c.254) was based in Alexandria. His thought emphasised one God, the Monad, as the sole ground and source of all being, material and immaterial alike. The Logos, who is one with the Father but separate from Him, is the mediator between God’s absolute unity and creation’s multiplicity; the Logos is a “secondary God.” The central motif of the Alexandrian school was the emphasis on the deity of Christ, especially as the necessary ground and presupposition of redemption, viewed primarily as man’s participation in the divine nature and life through theosis. For Origen, a pre-existent soul was united to the Logos and became inseparable with him as fire and hot iron, and this soul became the meeting point between the infinite Word and human nature (the body). In his exaltation, the Son of Man ceased to be other than the Logos and became identically one with Him.
Out of this line of thinking came Athanasius’ emphasis on theosis, but it was also open to the interpretation which Arius put on it – namely that the Son was a creation, the first born of creation. This view, which Arius supported with his own personal reading of Scripture, gained much support, and despite Nicaea in 325 ruling he was wrong, his supporters continued to argue the case for long afterwards.
Arius had human logic on his side, which accounts for the success of his ideas. There was only one God, that was the Father. He was greater than the Son (John 14:28), and therefore it followed that Son was a creation – another form of subordinationism. It explained much – but as Athanasius never tired of pointing out, it did not explain hiw the Logos was in the beginning with God, or how we could be redeemed by a creature. It was the fact that the Logos had become ‘sarx’ which redeemed our sinful flesh.
As Geoffrey has pointed out in the small war carried out in his part of the blog, the Pope did not summon Nicaea and it was not subject to his approval. He also did not know about the Constantinople Council of 381 which modified it until long afterwards.
The problem with Nicaea lay with the use of the non-Scriptural word, homoousios (of one substance) rather than the word preferred by the semi-Arians, homoiousios (of similar substance). If the Son really as, as Nicaea claimed, of the same substance as the Father, the question arose of how that substance related to the human flesh of Jesus. Antioch’s answer, that the Spirit indwelt in the body in a special way was not agreable to the idea of the prexistent Logos being one with God in the beginning; Alexandria’s answer was not clear on this point, and ran the risk of it being assumed that Christ’s humanity was submerged by the Divinity. Indeed, Apollinarius of Laodicea (d. 390) argued that Jesus Christ had no human mind and that the Logos had taken its place.
It was to deal with these problems that the Emperor Theodosius summoned a Council at Constantinople in 381.