What is the Trinity?

God & the TrinityIn theological review

The short answer

The Trinity is the Christian confession that there is one God, and that this one God is Father, Son, and Holy Spirit, three persons, each fully God, equal in power and glory. The word itself is not in the Bible. The reality is taught everywhere in it, and the church forged the word to protect what the Bible says from being flattened in either direction.

The fuller answer

Hold the two halves together, because Scripture insists on both. First, there is one God. Hear, O Israel: The LORD our God, the LORD is One. Christianity is not three gods, and it never has been.

Hear, O Israel: The LORD our God, the LORD is One.

Deuteronomy 6:4 (BSB)

Second, the one God is Father, Son, and Holy Spirit together. At the end of Matthew's Gospel, Jesus sends his followers to baptise in the name, singular, of the Father and of the Son and of the Holy Spirit. One name, three persons named in it. Jesus can also say, I and the Father are one, and yet pray to his Father as someone other than himself. The Bible does not let us merge the persons into one actor wearing masks, or split them into three separate beings.

Therefore go and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit,

Matthew 28:19 (BSB)

I and the Father are one.

John 10:30 (BSB)

The church's settled wording came at Nicaea and after. The Nicene Creed confesses one God the Father Almighty, one Lord Jesus Christ who is very God of very God, begotten not made, of one substance with the Father, and the Holy Spirit as the Lord and Giver of life, worshipped and glorified together with the Father and the Son. The Westminster Shorter Catechism says it in a single sentence: there are three persons in the Godhead, the Father, the Son, and the Holy Ghost, and these three are one God, the same in substance, equal in power and glory.

Sources

Berean Standard Bible (BSB)
The Nicene Creed (AD 325, enlarged 381)
The Westminster Shorter Catechism (1647)

Review status: in-theological-review. Every Contend page passes a human theological review against the Statement of Faith before it is published as approved teaching. This section is in that queue.

Dig deeper

No answer here is a dead end. Follow the question on, test it in practice, or work the method yourself on the Dig deeper page.

Who is the Holy Spirit?The Holy Spirit is God himself, the third person of the Trinity, not a force, a feeling, or God's power in the abstract. He is there at creation, hovering over the waters. He speaks, teaches, and can be lied to, and when Peter confronts Ananias he says the lie told to the Holy Spirit was a lie told to God.Is Jesus God?Yes. The New Testament calls Jesus God in plain words, shows him doing what only God does, and records him receiving the worship that belongs to God alone. That is why the church at Nicaea confessed him as very God of very God, of one substance with the Father, and why Chalcedon confessed him as truly God and truly man in one person.What is God like?God is spirit, eternal, unchanging, all powerful, holy, just, good, and true. And he is love. Scripture gives his character in his own words and deeds rather than in our guesses: he is the I AM who always is, the Maker who never tires, and the Father who so loved the world that he gave his Son.Lesson: I believe in God, the Father almightyThe Creed opens by naming who God is before it says anything about us. Take the first line apart, word by word, with the Scripture under each word.