What Is the Trinity?

The Nicene Creed says:

“We believe in one God, the Father Almighty, Maker of heaven and earth, and of all things visible and invisible; And in one Lord Jesus Christ, the Son of God, the only-begotten, begotten of the Father before all ages, Light of Light, true God of true God, begotten, not made; of one essence with the Father; through Whom all things were made . . . And we believe in the Holy Spirit, the Lord, and Giver of Life, Who proceeds from the Father, Who with the Father and the Son is jointly worshipped and jointly glorified . .”

What do we know about the Trinity?

There Is One God

Deuteronomy 6:4
“Hear, O Israel! The Lord is our God, the Lord is one!”

The Scriptures are clear that there is one and only one God. The term “one” (Hebrew ’eḥāḏ) may be understood as a “oneness of unity” (only by way of illustrating the meaning of the word ’eḥāḏ and not as an illustration of the Trinity cf. Gen. 2:24 e.g. the oneness of man and wife).

There Are Three Persons

Let’s take a quick look at how different passages in the Bible identify each member of the Trinity as “God.”

The Father Is God

1 Corinthians 8:6a
Yet for us there is but one God, the Father, from whom are all things and we exist for Him.

Ephesians 4:6
one God and Father of all who is over all and through all and in all.

The Son Is God

John 1:1–3
In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God. All things came into being through Him, and apart from Him nothing came into being that has come into being.

John 8:58
Jesus said to them, “Truly, truly, I say to you, before Abraham was born, I am.”

This is the most direct claim to deity made by Jesus. In this declaration Jesus is affirming his preexistence, which is in itself a claim to deity. Even more startling than that, he is claiming to be “I AM.” The Greek expression ego eimi is the emphatic first person singular for the verb “to be” and reflects the Hebrew ’ehyeh which is the equivalent to ego eimi, that is, the first person singular for the verb “to be.” When Jesus spoke those words, everyone who heard him would immediately have thought of the text in Exodus 3:14 where God declared his name to Moses as “I AM THAT I AM.” In short, Jesus was making a claim, not just to deity, but to be Yahweh. The name Yahweh is actually the third person singular for the verb “to be”—He Is.

The Spirit Is God

Matthew 12:31–32
“Therefore I say to you, any sin and blasphemy shall be forgiven people, but blasphemy against the Spirit shall not be forgiven. Whoever speaks a word against the Son of Man, it shall be forgiven him; but whoever speaks against the Holy Spirit, it shall not be forgiven him, either in this age or in the age to come.”

Acts 5:3–5
But Peter said, “Ananias, why has Satan filled your heart to lie to the Holy Spirit and to keep back some of the price of the land? You have not lied to men but to God.” At first, when Peter rebuked Ananias for his duplicity, he accused Ananias of lying to the Holy Spirit, and then in reiterating this indictment, he asserted that Ananias had lied to God. Peter was not accusing Ananias of two lies but one. Peter’s intention was not to make a theological point but to emphasize the seriousness of Ananias’ actions: to lie to the Holy Spirit is to lie to God.

The Scriptures are clear that there are three (persons) who may rightly be called God. Paul’s assertion that “there is but one God” establishes his belief in the one God based on the monotheism of the Old Testament. His reference to “the Father” is not meant to say this one God is the Father only, but that “the Father” is God. Other passages indicate that “the Son” is God and yet other passages indicate that “the Spirit” is God. This is not to suggest that there are three gods (i.e. tritheism) but that each one of the persons may rightly be called God. At the same time, the three are not merely three different names of the one God, as if there are times when the one God is call “Father,” and at other times he is called “the Son,” and yet other times he is called “the Holy Spirit” (i.e. modalism). The Scriptures reveal that there is One God (substance, essence; Greek ousia) in three Persons (subsistence; Greek hypostasis).

While the term “Trinity” is not used in the Bible, the Scriptures clearly reveal that there is one God, and just as clearly, they speak of three who may be rightly called God, and the three each have the characteristics of personhood. The Father, the Son and the Spirit each possess knowledge, show emotion, demonstrate will. The creedal statement—one God in three persons—is an accurate summary of what the Bible says about the one God who is the Father, the Son and the Spirit. In short, the doctrine of the Trinity is not imposed upon the texts of Scripture but emerges from what the Scriptures reveal about the one God and the three, who are distinct persons who deserve to be called God.

Old Testament Indications of the Trinity

There are no texts in the Old Testament that explicitly teach the Trinity. There are texts that can be seen as indications of, and which are in harmony with, the doctrine of the Trinity.

Indications of a Plurality in God

Genesis 1:26a
Then God said, “Let Us make man in Our image, according to Our likeness.”

Genesis 3:22a
Then the Lord God said, “Behold, the man has become like one of Us, knowing good and evil.”

Genesis 11:7
Come, let Us go down and there confuse their language.”

Isaiah 6:8a
Then I heard the voice of the Lord, saying, “Whom shall I send, and who will go for Us?”

In Genesis 1:26 God is speaking and the Hebrew text uses a first-person plural verb to describe that speaking, in the expression “Let us make.” Also, God uses a plural pronoun “our” when he refers to the “image” in which he is making man. Again, in Genesis 11:7 God uses a first-person plural verb: “let us go down.” In both Genesis 3:22, and Isaiah 6:8 God uses a plural pronoun (“Us”) to refer to himself. As noted in the name “Elohim,” these plurals may be indications of majesty and intensity, but with the clearer revelation of the Trinity given in the New Testament these texts seem to reveal a divine acknowledgement of his actual plurality.

Indications in Messianic Prophecy

Isaiah 61:1a
The Spirit of the Lord god is upon me,
Because the Lord has anointed me.

In this text the Messiah is speaking. (This text was read by Jesus in the synagogue at Nazareth. On that occasion he affirmed that the prophecy was fulfilled in his ministry [cf. Luke 4:16–21].) The Messiah is describing his empowerment by the Spirit and his commission by Yahweh. In this he makes reference to the Lord (Yahweh) and to the Spirit of the Lord (Yahweh) in such a way that these titles may be understood to refer to two distinct entities, both of which are identified by the name Yahweh. If the Messiah is still speaking through verse 8 (“For I, the Lord (Yahweh), love justice”) then he identifies himself by the name Yahweh. Again, this is an indication of a plurality in God and prepares for the full revelation of the Trinity in the New Testament.

Indications in the New Testament

How does the New Testament point to God being trinitarian? Let’s look at some ways.

Three Names

Matthew 28:19
Go therefore and make disciples of all the nations, baptizing them in the name of the Father and the Son and the Holy Spirit.

2 Corinthians 13:14
The grace of the Lord Jesus Christ, and the love of God, and the fellowship of the Holy Spirit, be with you all.

The references in Scripture to the names (Father, Son, Holy Spirit) and the separate identities indicated (Jesus Christ, God, Holy Spirit) within one verse is significant. These are indications that each name stands for a distinct person and each identity belongs to a distinct person, Consequently, this is indicative of the reality of the Trinity. In these texts the Trinity is not something that is being argued, rather it is simply assumed. These are the kind of texts that were studied and debated by the scholars and bishops of the church in the second through the fourth centuries and those debates led to the orthodox creeds of the church.

What the church later succinctly articulated in creeds (such as the Nicene-Constantinopolitan Creed 381 AD) is squared based on what the church read in the New Testament. In other words, the Trinity was not invented by the framers of the creeds, but it was discerned by them to be the teaching of Scripture.