Sabellian (christology)

In Christianity, Sabellianism in the Eastern church or Patripassianism in the Western church (also known as modalism, modalistic monarchianism, or modal monarchism) is the nontrinitarian or anti-Trinitarian belief that the Heavenly Father, Resurrected Son, and Holy Spirit are three different modes or aspects of one monadic God, as perceived by the believer, rather than three distinct persons within the Godhead—that there are no real or substantial differences among the three, such that there is no substantial identity for the Spirit or the Son. Modalistic monarchianism has been generally understood to have arisen during the second and third centuries, and to have been regarded as heresy after the fourth, although this is disputed by some. The term Sabellianism comes from Sabellius, who was a theologian and priest from the 3rd century. Historic Sabellianism taught that God the Father was the only true existence of the Godhead, a belief known as Monarchianism. One author has described Sabellius' teaching thus: "The true question, therefore, turns on this, viz., what is it which constitutes what we name ‘person’ in the Godhead? Is it original, substantial, essential to divinity itself? Or does it belong to and arise from the exhibitions and developments which the divine Being has made of himself to his creatures? The former Sabellius denied; the latter he fully admitted."

Sabellianism has been rejected by the majority of Christian churches in favour of Trinitarianism, which was eventually defined as three distinct, co-equal, co-eternal Persons of One Substance by the Athanasian Creed, probably dating from the late 5th or early 6th century. The Greek term homoousian or "con-substantial" (ὁμοούσιος) had been used before its adoption by the First Council of Nicaea. The Gnostics were the first to use the word ὁμοούσιος, while before the Gnostics there is no trace at all of its existence. The early church theologians were probably made aware of this concept, and thus of the doctrine of emanation, taught by the Gnostics. In Gnostic texts the word ὁμοούσιος is used with the following meanings:

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