Sabellianism

In Christian theology, Sabellianism is the belief that there is only one Person ('hypostasis' in the Greek language of the fourth century Arian Controversy) in the Godhead. For example, Hanson defines Sabellianism as the "refusal to acknowledge the distinct existence of the Persons" and "Eustathius was condemned for Sabellianism. His insistence that there is only one distinct reality (hypostasis) in the Godhead, and his confusion about distinguishing Father, Son and Holy Spirit laid him open to such a charge." Condemned as heresy, Sabellianism has been rejected by the majority of Christian churches.

== Monarchianism == Sabellianism appeared for the first time in the second century in the form of Monarchianism. While "this movement called themselves 'Monarchians', the Greek Fathers called them 'Sabellians', as Sabellius was the person who has put this doctrine in its philosophical form."