The heresy
propagated by Arius denying the Divinity of Jesus Christ. Following views
which Gnostics had popularized, he regarded the Son of God as standing
midway between God and creatures; not like God without a beginning, but
possessing all other Divine perfections, not of one essence, nature,
substance with the Father and therefore not like him in Divinity; an
attribute of the Divine nature, the Logos, or Word, Reason. The heresy for a
time threatened to rend asunder the Catholic Church, especially when favored
by the emperors of the East. It was the root source of many heresies. Its
antagonist Athanasius (296-373) contended for half a century for the term
consubstantial (Greek: Homoousion, one and the same, as
against Homoiousion, like only) to express the identity of the Son in
essence, nature, substance with the Father, which was adopted at the Council
of Nicaea, 325. This decision established the doctrine of the Divinity of
Christ, and although it did not end the struggle of the Arians for
ascendancy, it defeated their efforts to anticipate Mohammed and to
introduce Unitarianism as Catholic belief.
New Catholic Dictionary