By Matthew Foley, ISOW Writer

One of the odd things about American Christianity is that several groups don’t often think about or address the Trinity in their preaching or teaching. The unique and beautiful relationship of the Father, Son, and Holy Spirit is rarely, if ever addressed, which may cause some to assume that it isn’t really that important.

The Trinity — a core component of Christian faith

But for the last 2,000 years, the doctrine of the Trinity has been considered a core component of what sets Christianity apart from other religions or belief systems.

Some groups in the U.S. argue that the Trinity wasn’t part of church doctrine until the church councils under the Emperor Constantine. These groups include the United Pentecostals who believe that God is not three Persons, but would simply say that Jesus is God. To them, the terms “Father, Son, and Holy Spirit” are just different titles or modes of operation for Jesus.

The Unitarians are another group that deny the Trinity and claim that Jesus is not God and the Holy Spirit is not a distinct person from God, but a manifestation of God.

What is the doctrine of the Trinity?

At the International School of the Word, we aim to tackle this issue head-on. We believe that the doctrine of the Trinity is a fundamental aspect of the Christian faith and that the idea shows up throughout Scripture, including what many might consider the least likely of places — the Old Testament.

The Athanasian Creed contains one of the longest and most important statements ever on the doctrine of the Trinity. It reads:

The Athanasian Creed

Now this is the catholic (universal) faith: We worship one God in Trinity and the Trinity in unity, neither confusing the persons nor dividing their essence. 

For the Father is a distinct person, the Son is another, and the Spirit is still another. 

But the divinity of the Father, Son and Holy Spirit is ONE, equal in glory, coeternal in majesty…

What quality the Father has, the Son has, and the Holy Spirit has.

The Father is uncreated, the Son is uncreated, the Holy Spirit is uncreated.

The Father is immeasurable, the Son is immeasurable, the Holy Spirit is immeasurable.

The Father is eternal, the Son is eternal, the Holy Spirit is eternal.

This Creed Continues and Goes Even Deeper

And yet there are not three eternal beings; there is but one eternal being. So too there are not three uncreated or immeasurable beings; there is but one uncreated and immeasurable being. 

Similarly, the Father is Almighty, the Son is Almighty, the Holy Spirit is Almighty. Yet there are not three almighty beings; there is but one Almighty being.

Thus the Father is God, the Son is God, the Holy Spirit is God.  Yet there are not three gods; there is but one God. 

The Father was neither made nor created nor begotten from anyone. The Son was neither made nor created; He was begotten from the Father alone. The Holy Spirit was neither made nor created nor begotten; He proceeds from the Father and the Son.

Accordingly there is one Father, not three fathers; there is one Son, not three sons; there is one Holy Spirit, not three holy spirits.

Nothing in this trinity is before or after, nothing is greater or smaller; in their entirety the three persons are coeternal and coequal with each other.

So in everything…we must worship their trinity in their unity and their unity in their trinity. [1]

Wow! That’s a mouthful! What a description!

The doctrine of the Trinity is the idea that one God is revealed in three persons and has been for all eternity. A more complicated way of saying that is that God is one in being and three in persons.

That may sound strange to people reading this for the first time. In this post, I’ll attempt to demonstrate how the Old Testament confirms that this is the proper understanding of who God is.

The Trinity in the Old Testament

There are two aspects to God described in the Old Testament: His oneness and His mysterious plurality. The second aspect may send up some red flags for those who disagree with the doctrine of the Trinity. But before you discount the idea, let’s see if the concept of the Trinity appears in the Old Testament.

The idea of the oneness of God appears early on in the Bible.

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

This is the concept of the “oneness” of God. But does God’s “oneness” mean He has no internal plurality?

Deuteronomy 6:4 is a statement similar to Nehemiah 9:6.

“You alone are the LORD; You have made heaven … the earth and everything on it …” —Nehemiah 9:6 NKJ

In other words, God — YHWH — is the only God. He made all things and He is completely distinct from His creation. Outside of YHWH, there is no other deity or god. But this doesn’t mean that God has no plurality in His internal being. That may seem strange, but let’s examine the text in Deuteronomy once again.

When Deuteronomy 6:4 says, “the LORD is one,” the word for “one” is echad, which can mean one mathematically, but can also mean one in unity, like Adam and Eve being made “one flesh” (Genesis 2:24).

“Let US make man in OUR image…”

A phenomenal example for the inner plurality of God appears in Genesis 1:26, when God says to Himself, “Let US make man in OUR image.” Notice the language. “Let US make man in OUR image.”

Who is God having a conversation with? Many scholars believe this to be the first hint of the Trinity in the Bible!

But the idea can also be found throughout the Old Testament, even in the prophets. An excellent example of this is in Isaiah 48:12, 16.

12 “Listen to Me, O Jacob, And Israel, My called:
I am He, I am the First, I am also the Last…

16 “Come near to Me, hear this: I have not spoken in secret from the beginning;
From the time that it was, I was there. And now the Lord God and His Spirit
Have sent Me.” —Isaiah 48:12-16 NKJ

Notice that the one who is talking is God, the one who created the world from the beginning. But later, the one speaking says that “the Lord God and His Spirit have sent Me.” Interesting. God is being sent by the “Lord God” and “His Spirit”.

Many scholars believe that the person speaking in Isaiah 48:16 is “the servant of the Lord” or Jesus Himself, and that this is a reference to Jesus talking about the Trinity!

Just to be clear here: this is one Person who is YHWH, describing how He was sent by two others who are also YHWH!

Many see this passage as a reference to the three persons of the Trinity: the Father (“the Lord God”), the Son (“has sent me”), and the Holy Spirit (“his Spirit”). This is a divine mystery that appears throughout the Old Testament.

The Three Mystery Figures in the Old Testament!

There are actually three characters that are talked about in the Old Testament that seem to refer to the same person.

  1. The Angel of the Lord.
  2. The Mystery Man (who seems to be the Angel of the Lord).
  3. The Word of the Lord.

The Angel of the Lord

First, there is “the Angel of the Lord.” He seems to be a messenger who is also referred to and has the same authority as the Lord Himself. This is the one who led the children of Israel through the wilderness, who stood in the cloud by day and pillar of fire by night (Exodus 14:19-25). It was this same “Angel of the Lord” that was the Lord Himself who visited Abraham (Genesis 22:11). This angel held the power not to forgive sin (Exodus 23:21), which according to Scripture only God can do (Mark 2:1-12).

This means that the Angel of the Lord seems to really be the LORD, but in a form that can be sent to earth and dwell at a single physical location.

The Mystery Man

Second, the Mystery Man seems to have similar authority and even may be the same as the Angel of the Lord. In Genesis 18, He appears with two angels to Abraham and Sarah, even eating dinner with them. Abraham calls him the Lord, and this eventually led to the conversation that Abraham had with God about the town of Sodom.

The passage clearly calls this “man” the Lord.

It is this same “man” that wrestled with Jacob at Peniel (Genesis 32:26-30). After this man would not reveal His name and left Jacob, Jacob declared “I have seen God face to face, and my life is preserved” (v 30).

This same man appeared to Samson’s parents and was also called the “Angel of the Lord” (Judges 13:15-16). In this verse, this man would not reveal His name but called it “wonderful,” which is pil’iy in Hebrew. This word is only ever used for God’s incomprehensible ways. The same word is used for the Messiah who will be called “Wonderful Counselor” (Isaiah 9:6).

The Word of the Lord

Then there is the “Word of the Lord.” The main thing to notice is that the “Word of the Lord” is often personified as coming to the prophets like a messenger. It isn’t just referred to as something God says, but something or someone who speaks for Himself:

“Now the word of the LORD came to Jonah the son of Amittai, saying …”
—Jonah 1:1 NKJ

“The word of the LORD that came to Hoses the son of Beeri …”
—Hosea 1:1 NKJ

“The word of the LORD that came to Micah of Moresheth … which he saw concerning Samaria and Jerusalem.” —Micah 1:1 NKJ

Each of these, the Angel of the Lord, the Mysterious Man, and the Word of the Lord, all indicate that God’s complex unity has three Persons revealed to humanity.

There is so much more that can be said of the presence of the Trinity in the Old Testament. Hopefully, this short post will help you think through many of these references.

The Unity and Plurality of YHWH are definitely present in the Old Testament. The Angel of the Lord, the Mysterious Man, and the Word of the Lord are all indicators that the Trinity is a correct understanding of God.

To find out more about the Trinity, check out the ISOW Bible College course titled: Theology of the Trinity. You can find it here.

To view courses in Spanish, click here.


[1] The Athanasian Creed, quoted by Mark Galli in A Great and Terrible Love…  The version included in this message appears on the website of the Christian Reformed Church