What is Unitarian?Unitarianism can be viewed as a form of Nontrinitarianism which is a form of Christianity that rejects the mainstream Christian doctrine of the Trinity. The teaching that God is three distinct hypostases or persons who are coeternal, coequal, and indivisibly united in one being, or essence (from the Greek ousia). Certain religious groups that emerged during the Protestant Reformation have historically been known as antitrinitarian, but are not considered Protestant in popular discourse due to their nontrinitarian nature. According to churches that consider the decisions of ecumenical councils final, Trinitarianism was definitively declared to be Christian doctrine at the 4th-century ecumenical councils, that of the First Council of Nicaea (325 AD), which declared the full divinity of the Son, and the First Council of Constantinople (381 AD), which declared the divinity of the Holy Spirit. In terms of number of adherents, nontrinitarian denominations comprise a minority of modern Christianity. The largest nontrinitarian Christian denominations are The Church of Jesus Christ of Latter-day Saints ("Mormons") and Jehovah's Witnesses.
Who is Jehovah?Jehovah is the proper name of the God of Israel in the Hebrew Bible and one of the seven names of God in Judaism. "Jehovah" was popularized in the English-speaking world by William Tyndale and other pioneer English Protestant translations such as the Geneva Bible and the King James Version. It is still used in some translations, such as the New World Translation, the American Standard Version, and Young's Literal Translation, but it does not appear in most mainstream English translations, as the terms "Lord" or "LORD" are used instead, generally indicating that the corresponding Hebrew is Yahweh or YHWH.