nontrinitarianism

Nontrinitarianism refers to Christian theological positions that reject the doctrine of the Trinity—the belief that God exists as three persons in one being: Father, Son, and Holy Spirit. In nontrinitarian systems, God is typically understood as a single person, with Jesus and the Holy Spirit present in roles or modes rather than as coequal persons within one Godhead.

Beliefs within nontrinitarianism are diverse. Common features include strict monotheism and a distinction between God the Father and Jesus Christ, with the Holy Spirit often understood as God's power, presence, or agent rather than a personal inhabitant of the Godhead. Attitudes toward Jesus's nature vary: some view him as a subordinate or created being, others regard him as divine in a sense that does not equate him with the Father.

Historically, nontrinitarian ideas appeared in early Christianity (notably in Arianism, which denied that the Son was of the same substance as the Father) and persisted alongside trinitarian debates through late antiquity. In modern times, several movements have identified as nontrinitarian, including Unitarianism and Unitarian Universalism, Jehovah's Witnesses, Christadelphians, and the Latter-day Saints (Mormons). Oneness or modalist Pentecostal groups also reject the traditional Trinity by teaching that Father, Son, and Holy Spirit are not three distinct persons but manifestations of a single divine person.

Today, nontrinitarianism remains a minority within Christianity and is represented by a variety of denominations and movements with differing doctrines about the Godhead, Jesus, and the Holy Spirit.