In most branches of ChristianChristianity, the Trinity is an entity consisting of God (the Father), Jesus Christ (the Son), and the Holy Spirit. Sometimes called the "Triume Godhead," most Christians do not consider the Trinity to be a Pantheon, as you would find in many polytheistic religions, but as "three persons in one God." This allows Christians to claim that they follow a monotheistic religion, while in essence worshipping three gods. The composition and nature of the Trinity has been a major topic of disagreement and confusion among Christians since it was adopted at the Council of Nicea in 325 C.E.
The Trinity is never mentioned by that name in the Bible. While God, Jesus, and the Holy Spirit are all mentioned separately throughout the New Testament, there is only one passage which provides support for Trinitarian doctrine: 1 John 5:7-8 , which scholars call the Johannine Comma:
7 For there are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one.
8 And there are three that bear witness in earth, the Spirit, and the water, and the blood: and these three agree in one.
This passage, the only Biblical support for the Trinitarian doctrine, is not found in the oldest and best Greek manuscripts of the New Testament, which instead read "These are three that bear witness: the Spirit, the water, and the blood, and these three are one." Scholars believe the Johannine Comma to be a later addition to the New Testament, inserted to justify the doctrines of the orthodoxy.
There have been a wide variety of different interpretations of the nature of the Trinity over the centuries.
Not all Christian denominations accept the doctrine of the Trinity.