At first, reading Arius’ Letter to Eusebius of Nicomedia, a reader is struck with a sense that Arius is being persecuted for a nuance, an inconsequential idea being debated among Christians of the time. A modern reader, who is inundated with worse heresies daily, may be struck by Arius’ weak support for his argument, and even his obsession with his persecutors (rather than his argument). His appeal to his friend, “orthodox Eusebius,” however, at first seems harmless.
Then, when one reads the thorough analysis of Athanasius, which presents the Arian viewpoint fairly and more thoroughly— not as a strawman— it becomes clear that “Arianism” was a very serious heresy, which, at such a seminal time, had the potential to lead many souls astray. What is at stake in this controversy is the Trinity Itself. If Arius is right, that Jesus, having been created, must therefore be “less” than God the Father (since God is eternal), then Christ is not actually consubstantial with the Father. This would mean his Passion, death and resurrection could not defeat death, just as God’s miracles in the Old Testament (or even the healing Jesus performed on earth) did not defeat death for mankind.
Athanasius cites John; to me, this ends the argument: “In the beginning was the Logos and the Logos was with God and the Logos was God. He was in the beginning with God. All things came to be through him, and apart from him not one thing came to be … and the Logos became flesh and dwelt among us …” (87, citing John 1). For Arius to be correct, John must be wrong. Athanasius was correct to compare Arius to Caiaphas.