May the grace of the Lord Jesus Christ, the love of God, and the fellowship of the Holy Spirit be with you all (2 Cor. 13:14).

Why would anyone who understands simple arithmetic believe what the Christian faith says about God?

Every major branch of the Christian church, whether Roman Catholic or Protestant, or Eastern Orthodox, teaches the doctrine of the Trinity.  According to this doctrine, there are three persons who are God:  God the Father, Jesus the Son, and the Holy Spirit;  and yet there is only one God.  As one ancient statement of faith, the Athanasian Creed puts it:  “The Father is God, the Son is God, the Holy Spirit is God.  Yet there are not three gods;  there is but one God.”

Isn’t that just a case of very bad arithmetic?  Already when you’re small, you learn that one plus one equals two and that two plus one equals three.  But it sounds like, in order to be a Christian and believe in the Trinity, you have to believe that somehow, one plus one plus one equals one.  That doesn’t seem to make much sense.  Why would anyone who believes in three divine persons keep insisting that there is only one God?

The reason Christians believe in the Trinity is that this is how God has revealed himself.  The Bible teaches that Father, Son, and Holy Spirit are each God, and at the same time Scripture is very emphatic there is only one God.

The oneness of God is taught very clearly throughout the Bible, beginning in the Old Testament.  Deuteronomy 6:4 says, “Hear, O Israel, the Lord our God, the Lord is one.”  In Isaiah 46:9 the Lord says, “I am God, and there is no other;  I am God, and there is none like me.”  The Old Testament continually insists that there is only one God, and prohibits worshiping anyone or anything else.

The New Testament part of the Bible is just as insistent as the Old Testament that there is just one God.  In 1 Corinthians 8:4 the apostle Paul declares, “We know that an idol is nothing at all in the world and that there is no God but one.”  Christians believe that God is one because God has revealed himself to be one.

At the same time, however, God’s Word reveals that three distinct persons are God.  Jesus commanded that his followers be baptized not simply in the name of God, but “in the name of the Father, and of the Son, and of the Holy Spirit” (Matthew 28:19).  At the end of his second letter to the Corinthians, the apostle Paul gave a blessing which Christian churches still echo today:  “May the grace of the Lord Jesus Christ, and the love of God, and the fellowship of the Holy Spirit be with you all” (2 Corinthians 13:14).  Throughout the centuries, Christians have been baptized and blessed in this threefold name, believing that Father, Son, and Holy Spirit are God, equal in divine majesty, power, and perfection.

I can’t begin to explore all the scriptures which declare Jesus to be equal with God, so I’ll mention just a few of the most obvious ones from the gospel of John.  Referring to Jesus as “the Word,” John 1:1 says, “The Word was with God, and the Word was God.”  Jesus acted as God’s equal when he exercised authority to forgive sins, and when he commanded the forces of nature through various miracles.  In talking to his Father in heaven, Jesus said, “And now, Father, glorify me in your presence with the glory I had before the world began” (John 17:5).  Jesus told some religious leaders, “Before Abraham was, I AM!”  He had existed from all eternity as God the Son, before Abraham was ever born.  The reason the religious leaders gave for crucifying Jesus was that he claimed to be equal with God.  Jesus was proved to be the Son of God in power when he rose from the dead.  After Jesus’ resurrection, when he showed himself to his disciples, Thomas said to him, “My Lord and my God!” (John 20:28)

The Bible teaches that Jesus is equal with God, and God’s Word also shows that the Holy Spirit is God.  The fact that the Holy Spirit is included in the Bible’s formulas for baptism and blessing along with the Father and the Son is strong evidence.  The Bible often refers to the Holy Spirit as “the Spirit of God” and also as “the Spirit of Christ.”  One story in the Bible which clearly shows the deity of the Spirit is a sad one found in Acts 7.  Ananias and Sapphira were a couple who made a donation to the church but lied about how much they kept for themselves in order to make their gift appear more generous than it really was.  Peter said, “You have lied to the Holy Spirit…  What made you think of doing such a thing?  You have not lied to men but to God.” (Acts 7:3-4)  According to the Bible, when you lie to the Holy Spirit, you are lying to God.  In other words, the Holy Spirit is God.

So there you have it:  three divine persons, yet united as one God.  This is what Christians believe because this is what God has revealed about himself.  God is three in a certain sense, but in another sense he is one.  It’s not that Christians can’t understand simple arithmetic.  It’s just that the God who has existed from everlasting to everlasting is much greater than any notions about him that we might come up with on our own, and he has revealed himself to be one God in three persons.  As the ancient creed puts it, “The Father is God, the Son is God, and the Holy Spirit is God.  Yet there are not three gods; there is but one God.”  Christians believe this about God because that is how God reveals himself in the Bible.  I’d like to explore with you what it means to say that God is three in one, and why it matters so much.

What does it mean to say that Father, Son, and Holy Spirit are all God, and yet there is only one God?

One of the easiest solutions to this great mystery is to say that there is really only one person who is God, and that “Father,” “Son,” and “Holy Spirit” are just three different titles for three different modes in which the one God operates.

For example, I am one person with several different roles and titles.  I’m “Dave” to my friends, “Daddy” to my daughters, and “Pastor” to many other people.  It’s easy to see that although “Dave” is David Feddes, “Daddy” is David Feddes, and “Pastor” is also David Feddes, there are not three David Feddeses, but one.  Those three titles simply refer to one man, myself, who has the three different roles of friend, father, and minister.

Is that what the Trinity is like?  Are Father, Son, and Holy Spirit simply three different roles played by the same divine person?  In this view, there really aren’t three divine persons at all.  There is only one, who goes by different titles, depending on what he is doing:  he is called Father in his work of creating and caring for people;  he is called the Son, or Jesus, when he is providing forgiveness of sin and victory over death;  and he is called the Holy Spirit in his work of living within Christians and making them more holy.  Father, Son, and Holy Spirit are really just different titles for three different roles that are fulfilled by the one God.  Just as I, David Feddes, can be a friend, a father, and a pastor and still be one person, so God can be Creator, Redeemer, and Sanctifier as one person.

Another variation on this approach of seeing God as one person in three different modes applies the names “Father,” “Son,” and “Holy Spirit” to three different phases in God’s career, so to speak.  Talking about God the Father, God the Son, and God the Holy Spirit would be similar to talking about Ronald Reagan the radio announcer, Ronald Reagan the movie actor, and Ronald Reagan the President.  This doesn’t mean there are three Ronald Reagans.  There’s just one, whose life included these three different career phases.

In much the same way, according to this approach, God is one divine person who has existed in three different phases.  Originally, he was the Almighty, invisible Father;  then, about two thousand years ago, he moved out of that phase to become a human being in the person of Jesus until his resurrection and ascension;  then, on Pentecost, God began a new phase of his career when he came upon the church as the Holy Spirit.

Now, ideas like this would certainly make it easy to understand how Father, Son, and Holy Spirit could be one God.  We have no problem understanding how one person could go through several different stages or careers, just as we have no problem seeing how a single person can fulfill several different roles.

But is this all that the Bible means when it teaches that Father, Son, and Holy Spirit are one God?  Hardly.  These ideas may seem very understandable and appealing, but they simply don’t take into account what the Bible teaches.  It is clear from God’s Word that Father, Son, and Holy Spirit are not simply titles for different modes in the existence of a single divine person.  Christians confess God in three persons, not God in three different roles or phases.  Father, Son, and Holy Spirit are three divine persons.

It is clear in the Bible that Father, Son, and Holy Spirit are not all the same person.  After Jesus was baptized, says the Bible, “he saw the Spirit of God descending like a dove and lighting on him.  And a voice from heaven said, ‘This is my Son, whom I love;  with him I am well pleased.'” (v. 16-17).  The voice from heaven was God the Father speaking to his Son; it wasn’t Jesus acting as a ventriloquist and causing a voice from heaven to talk about himself.  Also, the Spirit that descended on Jesus is not the same person as Jesus.  Jesus is a person distinct from the Father and distinct from the Holy Spirit.

Jesus often talked to his Father in heaven.  He wasn’t just talking to himself when he did this.  He was talking to another divine person, the Father with whom he had shared divine glory from all eternity.  God the Father and God the Son are distinct.  God the Father did not become a baby, live on earth as a man, and die on a cross, and neither did God the Holy Spirit.  God the Son did that in the person of Jesus Christ.

God the Father and God the Son are each divine persons distinct from each other, and the Holy Spirit is also a distinct divine person.  Jesus told his disciples, “I will ask the Father, and he will give you another Counselor to be with your forever–the Spirit of Truth” (John 14:16-17).  The Bible clearly teaches that Father, Son, and Holy Spirit are distinct persons, and that each of these persons is fully divine, as we’ve already seen.

Well, then, if that’s that case, if we agree that Father, Son, and Holy Spirit– three distinct persons–are God, why don’t we just state the obvious and say there are three Gods?  When, for example, the Greeks said that Zeus, Apollo, and Hermes were all gods, they didn’t pretend that these three were somehow one God.  So how are Father, Son, and Spirit one God, any more than the gods of ancient myth?

To begin with, the Bible teaches equality of the three persons within the oneness of God.  In the legends, one god was the chief deity in the pecking order.  For the Greeks, it was Zeus who had the most power;  for the Romans, it was Jupiter;  for the Vikings, Odin the god who was superior to the others.  In contrast to all this, no person in the Trinity lacks any of the divine attributes of the others or is inferior.  Within the being of the one true God, Father, Son, and Holy Spirit are all equally infinite in power, splendor, wisdom, love, and holiness.  All are equally eternal, uncreated, without beginning or end.  This is true because all three persons share the same divine essence.

Another obvious difference between the one Triune God and the false gods is that in the Trinity there is a complete oneness of will, a total unity of purpose, a perfect harmony.  Father, Son, and Spirit never disagree or squabble.  That’s a far cry from the mythical gods who were constantly bickering and doing things behind each other’s backs.  In the oneness of will that exists in the Trinity, the Son never contradicts the will of the Father.  It’s never the case that the Father wants one thing, the Son want another, and the Spirit something else.   Jesus the Son came to do the will of his Father.  Likewise, the Holy Spirit always does his work in perfect cooperation with the purposes of the Father and the Son.  Father, Son, and Holy Spirit are one in will and purpose.

The oneness of God also means that there is no division of authority, where each divine person controls a different aspect of life.  In the ancient superstitions, one god would be the god of war, another the god of sex and fertility, another the god of wisdom, and so forth.  So, depending on what you needed at the time, you would try to get on the good side of the particular god who controlled that part of life.  The great truth that God is one means that he is Lord over every aspect and dimension of life, not just in some specialty.  He is the creator and master of all things.

Since God is one, you can’t get out of his territory and into the territory of a god that will perhaps be different.  Father, Son, and Holy Spirit don’t each rule different parts of the universe.  The Trinity rules as one God with no division of territory.  The Bible tells about a time when the Lord helped his people to win an important battle over superior forces.  The people opposing them weren’t about to give up, however.  They figured that they had lost the first battle only because it had been fought in the hills.  The king’s officials advised him, “Their gods are gods of the hills.  That is why they were too strong for us.  But if we fight them on the plains, surely we will be stronger than they” (1 Kings 20:23).  They figured the god who controlled what happened in the hills might not be so strong on the plains, so they fought the next battle on the plains–and they were defeated even more soundly than they were the first time.  They learned the hard way that there is just one God who is equally in charge on both hills and plains.

God’s Word simply won’t permit us to talk about three gods, even though there are three divine persons.  We’ve seen that Father, Son, and Holy Spirit are united in full and equal deity;  they are united in will and purpose; they are united in joint reign over all things.  But the oneness of the Trinity transcends even these aspects of unity.  There is a unity within the Trinity which underlies these things, and which is deeper, stronger, and also more mysterious.

The Bible compels us to believe that the three divine persons share in the same divine being or essence.  Father, Son, and Holy Spirit are not the same person; but they are united in the same being.  They are distinct from one another, but never divided or separated or independent from each other.  All three share the same divine essence and are united as one divine being, from eternity past, right now, and into the eternal future.

This oneness of being is somehow very closely related to a marvelous oneness of love, a love that has forever united the persons of the Trinity with each other.  There is no way we can fully describe or understand this mysterious union of Father, Son, and Spirit, since God transcends any earthly comparison we might use.  But maybe we can see just a glimmer of this unifying love if we think of a husband and wife who have enjoyed a long and loving marriage.  Sometimes both will have the same thought at the same time, or one will know how the other is feeling without being told.  They’ve been together so long, loving each other so much, knowing each other so well, that there are times when they almost think and feel and act as one.

Now take that and multiply it infinitely.  The love among Father, Son, and Holy Spirit is immeasurably greater than the love of a husband and wife.  Not only that, but Father, Son, and Holy Spirit have existed together in perfect harmony, not just for several decades, but for all eternity.  The three divine persons have forever been united by their mutual love and also in the very substance of their being.

Since this blessed Trinity is who God is, we see why it is necessary to trust Jesus in order to have a right relationship with God.  It simply won’t do to say, “Well, even if some people don’t believe in Jesus, at least we all believe in the same God.”  Is that so?  How can you possibly reject Jesus and be right with God the Father?  If you don’t love Jesus, you can’t love the Father.  As Jesus himself said, “I and the Father are one…  the Father is in me, and I in the Father”  (John 10:30, 38).  Christ plainly declared, “He who hates me hates my Father as well” (John 16:23).  So you can’t reject any member of the Trinity without rejecting the one God, because the Trinity is God.  There is no God that exists apart from the oneness of Father, Son, and Spirit.

Jesus says, “No one comes to the Father except through me” (John 14:6), and he also says, “No one can come to me unless the Father who sent me draws him” (John 6:44).  Salvation is a work involving the Father and the Son.  And the Father and Son do nothing apart from the Holy Spirit.  The Bible says, “And if anyone does not have the Spirit of Christ, he does not belong to Christ” (Romans 8:9).

Each person of the Trinity is essential in the work of salvation and in establishing God’s Kingdom of love.  Ultimately, God’s purpose is that his people become one in love in a way that somehow reflects the loving oneness within the Trinity (John 17:11).  God is love, both in the eternal love that the persons of the Trinity have for each other, and also in the way he relates to his people.  There is nothing more wonderful or more necessary than to be drawn into living faith in this marvelous God.  I pray that as I have shared with you what God says about himself in his Word, the Lord has been drawing you into a living, saving faith in himself.

If you’re already a Christian, if you confess one God in three persons, if you’ve been baptized into the name of Father, Son, and Holy Spirit, I hope that even now you are filled with awe and deep joy at that wonder of our God, and have a powerful desire to know him better and better.  In our minds, we can’t fully understand the deep truths which the Triune God reveals about himself, but in our hearts, we can bow down in worship before the majesty and mystery of these three infinite, magnificent, eternal persons united in a perfect oneness that surpasses all human imagination or description.  And we can look forward to the day when we will no longer see through a glass darkly, but see face to face and have all of eternity to enjoy the life and love of the blessed Trinity.


Triune God, open our minds to believe what you reveal about yourself, even when we don’t fully understand it.  Father, Son, and Holy Spirit, we adore and worship you for who you are and for all that you have done.  May the grace of the Lord Jesus Christ, and the love of God, and the fellowship of the Holy Spirit be with us all.  Amen.

By David Feddes. Originally broadcasted on the Back to God Hour and published in The Radio Pulpit.