The name comes from the merging of two groups, the unitarians and the universalists who shared the same ideology.
Unitarians do not believe in the Trinity...
http://en.wikipedia.org/wiki/Unitarianism
Unitarianism is a Christian theological movement, named for its understanding of God as one person, in direct contrast to Trinitarianism which defines God as three persons coexisting consubstantially as one in being.[1]
For most of its history, Unitarianism has been known for the rejection of several orthodox Protestant doctrines besides the Trinity,[2] including the soteriological doctrines of original sin and predestination,[3][4] and, in more recent times, biblical inerrancy.[5] In J. Gordon Melton's Encyclopedia of American Religions it is classified among "the 'liberal' family of churches".[6]
The first Unitarians, although not called Unitarians initially, were found in Poland and Transylvania from the 1540s onwards, though many of them were Italians.[7][8] In England the first Unitarian Church was established in 1774 on Essex Street, London, where today's British Unitarian headquarters are still located.[9] The first official acceptance of the Unitarian faith on the part of a congregation in America was by King's Chapel in Boston, from where James Freeman began teaching Unitarian doctrine in 1784, and was appointed rector and revised the Prayer Book according to Unitarian doctrines in 1786.[10]
"Unitarianism" is a proper noun and follows the same English usage as other theologies that have developed within a religious movement (Calvinism, Anabaptism, Adventism, Wesleyanism, etc.).[11] The term existed shortly before it became the name of a religious movement, and thus occasionally it is used as a common noun and would describe any Christology (i.e. understanding of Jesus Christ) that denies the Trinity or believes that God is only one person. In that case it would be a monotheistic belief system not necessarily associated with the Unitarian religious movement.[12][13][14] For example, the Unitarian movement has never accepted the Godhood of Jesus, and therefore does not include those nontrinitarian belief systems which do — such as Oneness Pentecostalism, United Pentecostal Church International and the True Jesus Church — that maintain that Jesus is God as a single person. Although these groups are unitarians in the common sense, they are not in the proper sense. To avoid confusion, this article is about Unitarianism as a religious movement (proper noun). For the generic form of unitarianism (the Christology), see Nontrinitarianism.
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