Biblical unitarianism

Biblical unitarianism (otherwise capitalized as biblical Unitarianism, sometimes abbreviated as BU) is a UnitarianChristian tradition whose adherents affirm the Christian Bible as their sole authority, and from it base their beliefs that God the Father is one singular being, and that Jesus is God's son but not divine.

Unitarian Christianity began in the Polish–Lithuanian Commonwealth and in Transylvania in the mid-16th century; the Christian denomination that emerged is known as the Unitarian Church of Transylvania, founded by the Unitarian preacher and theologian Ferenc Dávid (c. 1520 – 1579). The creed of the Unitarian Church of Transylvania is:

"I believe in one God, the creator of life, our providential Father. I believe in Jesus, the best son of God, our true teacher. I believe in the Holy Spirit. I believe in the mission of the Unitarian Church. I believe in the forgiveness of sins and in eternal life. Amen."

The early Unitarian Christian leader Demeter Hunyadi led the effort to catechize the faithful. The first Unitarian Christian confession of faith was the Consensus Ministrorum, which holds to a Unitarian view of God and teaches that Jesus Christ should be adored; the confession of faith titled the Complanatio (1638) established the necessity of infant baptism and reception of the eucharist. The widely used Racovian Catechism (1605) of the Polish Brethren explicated the Unitarian Christian faith from a Socinian perspective, supporting its doctrine with proof-texts from the Bible.

Used to herald this historic Unitarian Christian faith that emerged after the Reformation, the term "biblical Unitarianism" is connected first with Robert Spears and Samuel Sharpe of the Christian Life magazine in the 1880s. As liberal Unitarian churches moved away from mainstream church traditions and, in some instances in the United States, towards merger with Universalism, bodies of traditional Unitarian Christians sought to distinguish themselves by using the terms "Biblical Unitarian" or "Unitarian Christian" or by asserting traditional definitions of the "Unitarian" denomination of Christianity.

The history of Unitarianism was as a "scripturally oriented movement" which denied the Trinity and held various understandings of Jesus. Over time, however—specifically, in the mid-19th century—liberal proponents of Unitarianism moved away from a belief in the necessity of the Bible as the source of religious truth. The nomenclature "biblical" in "biblical Unitarianism" is to identify the groups that did not make such a move, and continue to herald the Unitarian Christian faith based on biblical teaching.