Arianism
“In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God. All things were made through him, and without him was not any thing made that was made” (vv. 1–3).
Modalistic monarchianism, the church determined early on, is heretical because modalism fails to take into account everything the Bible says about God. Scripture clearly distinguishes the Father from the Son from the Spirit (Luke 10:22; John 14:26; 15:26). Even though all three persons of the Trinity are fully equal in power, dignity, knowledge, and every other attribute that makes God who He is, each person possesses some properties that the others do not share. According to the ancient creeds, the Father is unbegotten, the Son is eternally begotten of the Father, and the Spirit proceeds eternally from the Father and the Son. These distinctions do not render any one of the persons of the Trinity “less God” than any of the others, but they are real distinctions. The persons of the Trinity are more than masks, offices, activities, modes, or ways of appearing. God is both one and three, albeit in different senses (R.C. Sproul, Truths We Confess, vol. 1, pp. 69–70).
Keeping the three persons properly distinct is essential, but at the same time we must not separate any of the persons from the one essence of our Creator. If we press the distinction too far, we can divide the Godhead into three gods or, like Arius, deny the deity of one of the persons. Arius provoked one of the greatest christological crises in the early church when he questioned the full deity of Christ in the early fourth century AD. Attempting to understand the sonship language of the New Testament, Arius relied too much on the human experience of sonship to illustrate the relation of the Son to the Father. Like human fathers, said Arius, God the Father existed before God the Son. Arius claimed that the Father begat the Son in His first act of creation: the Son was created before all other creatures and maintains an exalted status as the agent through whom everything else was created. Nevertheless, as worthy as He is, the Son is, in the final analysis, just a creature, according to Arius.
The early church rightly understood that if the Son is not fully God, He cannot truly mediate salvation to us. Turning to passages such as John 1:1–18, the early church affirmed the full deity of the second person of the Trinity, settling the question at the Council of Nicea in AD 325. Since that day, the orthodox, universal church has confessed that the Son is of the same essence (homoousios) as the Father.
Coram Deo
Arius’ teaching — Arianism — is alive today in cults such as the Jehovah’s Witnesses. It may also be held unwittingly by Christians who have not received good teaching and believe, implicitly, that the Father is a “higher” God than the Son. But we must always be clear that the Father, Son, and Spirit are fully equal as to their essence. One is not “more God” than the other, but all are worthy of our unreserved worship and obedience.