In Religion, the Trinity is a central doctrine of most branches of Christianity. Historically, as evidenced by the Nicene and Apostle's Creeds used by most of Christianity, the Holy Trinity refers to what Christians say are the three persons of God, the Father, the Son, and the Holy Spirit.
The doctrine of the Trinity does not appear explicitly in the Bible (indeed not even the word itself is found there), but there are many passages that believers in it point to as implying it.
As it exists today the doctrine developed over the centuries as a result of many controversies, such as Arianism, Sabellianism, and Adoptionism. These controversies were often settled at the Ecumenical Councils, whose creeds affirm the doctrine of the Trinity.
According to the Athanasian Creed, each of these three divine Persons are said to be eternal, each said to be almighty, none greater or less than another, each said to be God, and yet together being but one God. According to the teachings of Eastern Orthodoxy and others, the three persons of the Holy Trinity share one Divine Nature. Other statements emphasize that these three "Persons" are not separate and distinct individuals but are three modes in which the divine essence exists. This is sometimes known as Modalism or Sabellianism. Some feminist theologians refer to the persons of the Holy Trinity with more gender-neutral language, such as Creator, Redeemer, and Sustainer.
The Father is often thought of as the God who acts throughout the Old Testament and talks to and through Christ in the New Testament. All three persons of the Trinity are believed to be clearly present and active in the Creation as described in Genesis 1 and 2 and in John 1. Eastern Orthodox theologians believe that Abraham's visit by three angels was in fact a visit by the three persons of the Holy Trinity. The Eastern Orthodox icon of the three youths in the fiery furnace (event recorded in the Book of Daniël indicates that the angel walking with them in the furnace was in fact Jesus Christ, the preincarnate second person of the Holy Trinity.
The Son is Jesus, who is described in the book of Hebrews chapter 1:2-3 as ...appointed heir of all things, through whom also He (meaning God) made the worlds; who being the brightness of His glory and the express image of His person..., whose sacrifice on the cross and subsequent resurrection ransomed souls from hell, opened the portal to heaven for those who want to go or both, depending on which Christian tradition one consults. He was both God and man, not considered to be some kind of phantasm or soulless possessed being, but was just like other humans except for also being God. The Chalcedonian Creed spells out the distinctions between Christ's divine nature and his human nature.
The Holy Spirit is sometimes thought of as the essence of God embodied as divine or inspired wisdom in people's lives, telling them the proper way to deal with the universe. Some believe that it is within everyone, the part of God that communicates directly with humans. The more traditional view is that the Holy Spirit is a distinct person, coeternal with the Father and the Son, no more or less imminent than the Father and the Son.
The three parts of the Holy Trinity are widely held to be coeternal, of the same substance, and yet inexplicably different. All are considered to be present at each stage in history.
In Eastern Orthodox theology, the distinction is often described as follows. The three persons of the trinity share the same divine essence, the same divine nature. (Because there is only one Divine Essence, and the three persons are undivided, there is only one God; thus Trinitarian Christianity remains monotheistic.) The difference between them is only that the Father begets the Son, and the Son is eternally begotten of the Father. The Holy Spirit eternally proceeds from the Father. The Son does not beget or proceed; the Father neither proceeds nor is begotten; the Holy Spirit nether begets nor is it begotten. There are no other differences. Note that the filioque clause inserted into the Nicene Creed by the Roman Catholic Church varies from this definition when it says that the Holy Spirit proceeds from both the Father "and the Son." Many Protestant groups also include the filioque clause in the Nicene Creed.
Despite this concept of the Trinity, Christianity is considered a monotheistic faith, though many theologians of other monotheistic faiths such as Judaism and Islam have found the concepts difficult to reconcile.
Most Christian groups believe in the Trinity, but some do not, including: the Church of Jesus Christ of Latter-day Saints, the Jehovah's Witnesses, Oneness Pentecostals, the Unification Church and Unitarian Universalists.
In the religion Dianic Wicca as well as other branches of Neopaganism, trinity refers to the Maiden, Mother and Crone (or Virgin, Mother and Crone), three versions of the Goddess and the three stages of a woman's life. This concept is itself derived from much earlier mythologies such as the multi-faceted aspect of Morrigan in Irish mythology and Frigg in Norse mythology. Trinity is also used by Egyptologists to describe the Ancient Egypt deities Osiris, Isis, and Horus.
Many Neopagans' concept of all Gods and Goddesses as aspects of a single divine being is similar to the Christian concept of the Trinity, but Neopaganism is not considered monotheistic. Many Hindus also believe that all their Gods and Goddesses are all aspects or part of a single divine being, but Hinduism is not considered monotheistic either.
Trinity is also the name of the central female character in the film The Matrix