What Is the Trinity and Why Does It Matter?

The trinity is one of the really hard concepts to understand about the Christian faith. What does it mean, really? Are there really three people who are God, or is there really only one God the way the Bible says?

If both three and one are true, how can they both be true at the same time? How does the whole thing work? Why is it so complicated? Why did people in the church fight so much about it? What difference does it make, as long as we love God and follow Jesus?

The idea of the trinity is never actually mentioned in the scripture, so what we know is what we’ve figured out from whatever clues we can find. The principles of the theological doctrine of the trinity say that

  1. each member of the trinity is individually God
  2. each member really is different from each other member, and
  3. there is only one God.

Early in the history of the church, it was agreed to describe the trinity as three persons sharing one substance.

This language about three persons and one substance was the solution to one of the biggest controversies in the early church. It was decided at the council that met in Nicea. We’ve heard that tempers ran high at that meeting. There’s even some indication in the historical record that there were fistfights in the halls. It seems that passion around controversy in the church hasn’t changed much over the centuries since, although the topics do change over time.

We don’t find many mentions in the bible of all three members of the trinity together. Usually we find each of them doing their own work in their own area of operation, in cooperation with the others. The best known mention of the three together is probably at the end of Matthew’s gospel in what is known as the great commission. Jesus says,

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)

Clearly, Jesus had an understanding of all three, separate but together.

Three different roles

One way of looking at the trinity is to consider the three persons as different aspects of the one God, each with the responsibility for doing different things. Paul, in the letter to the Romans, talks about the way the three interact with us. He says,

Therefore, since we have been justified through faith, we have peace with God through our Lord Jesus Christ, through whom we have gained access by faith into this grace in which we now stand. (Romans 5:1-2)

hope does not disappoint us, because God has poured out his love into our hearts by the Holy Spirit, whom he has given us. (Romans 5:5)

Through Jesus we receive forgiveness and reconciliation with God, and through the Holy Spirit we receive God’s love.

We know that all three members of the trinity were present at the time of creation and that each of the three had a different job. Paul describes the Father’s role by saying,

for us there is but one God, the Father, from whom all things came and for whom we live; (1 Corinthians 8:6)

Psalm 8 is a wonderful appreciation of the richness of the Father’s work. The Psalmist says:

You have set your glory above the heavens. … When I consider your heavens, the work of your fingers, the moon and the stars, which you have set in place, what is man that you are mindful of him, the son of man that you care for him? You made him a little lower than the heavenly beings and crowned him with glory and honor. You made him ruler over the works of your hands; you put everything under his feet: all flocks and herds, and the beasts of the field, the birds of the air, and the fish of the sea, all that swim the paths of the seas.

The Father Creator is the original source of all things.

The Father is the originator, but even at the beginning of all things, Jesus was the one to provide the form for the substance of our world. As John explained it,

In the beginning was the Word, and the Word was with God, and the Word was God. He was with God in the beginning. (John 1:1-2)

This other one who was there during creation, was the same one who took on a human body, lived a human life, and was known among us as Jesus. John goes on to say,

Through him all things were made; without him nothing was made that has been made. In him was life, and that life was the light of men. (John 1:3-4)

The wisdom, the understanding, and the brilliant intelligence of God were all part of that work, bringing all things into being. The one who became Jesus embodied in himself God’s wisdom—God’s plan and God’s design for creation.

In Proverbs there’s also a description of the presence of God’s wisdom during those earliest moments of creation. The passage from Proverbs says,

I was there when he set the heavens in place, when he marked out the horizon on the face of the deep, when he established the clouds above and fixed securely the fountains of the deep, when he gave the sea its boundary so the waters would not overstep his command, and when he marked out the foundations of the earth. (Proverbs 8:27–29)

The Father and the Son were there together, working together.

But even at the very beginning, we can’t leave out the Holy Spirit. The first verses of Genesis tell us that even then the Spirit was active, moving in and through creation do the work under the Father’s direction. We hear, at the beginning of Genesis, what this time of creation was like. The Hebrew word that is sometimes translated as “wind”, (רוּחַ) ruach, is also translated as Spirit. In the New International Version translation, the first two verses of Genesis are:

In the beginning God created the heavens and the earth. Now the earth was formless and empty, darkness was over the surface of the deep, and the Spirit of God was hovering over the waters. (Genesis 1:1-2)

Was all this creating work or fun?

Have you ever thought of that original creation as fun? We know that God worked on creation for six days, or at least for six eras of time that were divided by the different kinds of work that were done in them. We know that God looked at the work from time to time and approved of it.

But Genesis doesn’t give us a picture of what it might have felt like to be part of the trinity at that time. The Father provided the creative power, the Spirit touched the specifics, and the Word provided the form and the design as things were made. But was it fun, or was it just another day’s work?

The Word that’s personified in Proverbs shows someone who purely enjoys the work of creation. Wisdom is included in each of the builder’s tasks, and is having a terrific time doing it all. Proverbs says,

I was the craftsman at his side. I was filled with delight day after day, rejoicing always in his presence, rejoicing in his whole world and delighting in mankind. (Proverbs 8:30–31)

The work of creation was a daily delight, and, moment by moment, the Creator got to enjoy the wonderful new things that are flowing into being. All the miraculous variety of objects and ideas must have great fun to savor and to enjoy as they appeared, one after the other.

Next time we wonder why God created all things, we have at least part of the answer. it was fun. Father, Son, and Holy Spirit got to enjoy themselves, working and creating together. In that critical time at the beginning of everything, all three members of the trinity were active, each doing the work that was uniquely their own.

Where was the trinity when Jesus was here?

During the time of Jesus’ life on earth, we also see all three members of the trinity active and working together. All three were there for Jesus’ baptism. When Jesus was baptized, the Holy Spirit came to him and descended on him. We hear in Mark’s gospel that

Just as Jesus was coming up out of the water, he saw heaven being torn open and the Spirit descending on him like a dove. And a voice came from heaven: You are my Son, whom I love; with you I am well pleased. (Mark 1:10-11)

All three were there, Father, Son, and Holy Spirit. The Father gave his blessing, and the Spirit anointed Jesus with power as he began his earthly ministry.

The Holy Spirit was a constant companion, descending on Jesus at his baptism. The Spirit led him out into the desert to be tempted, filled him with strength to begin his ministry in Galilee, and provided the power for his miraculous healings.

During his lifetime, Jesus was in frequent communication with the Father through prayer. We hear in Luke’s gospel that

One of those days Jesus went out to a mountainside to pray, and spent the night praying to God. (Luke 6:12)

It took a while for the disciples to get used to the idea that Jesus valued his time of prayer. We hear from Mark that early in their time together,

Very early in the morning, while it was still dark, Jesus got up, left the house and went off to a solitary place, where he prayed. Simon and his companions went to look for him, and when they found him, they exclaimed: “Everyone is looking for you!” (Mark 1:35-37)

Private time for prayer can be hard to come by, for Jesus as well as for us.

Jesus spoke about his close relationship with the Father during his ministry. He told the disciples,

I came from the Father and entered the world; now I am leaving the world and going back to the Father. (John 16:28)

He said publicly to the disciples and the crowd,

I and the Father are one. (John 10:30)

and he also told them,

if I do it, even though you do not believe me, believe the miracles, that you may know and understand that the Father is in me, and I in the Father. (John 10:38)

This didn’t mean that Jesus and the Father were the same person, sharing the same thoughts. We know that Jesus had thoughts and desires that came from his human nature, and they were uniquely his own. But when there was a difference between his own desires and those of the Father, Jesus yielded to the Father every time. At the most painful time in the garden, Jesus expressed his own feelings to the Father.

Going a little farther, he fell to the ground and prayed that if possible the hour might pass from him. “Abba, Father,” he said, “everything is possible for you. Take this cup from me. Yet not what I will, but what you will.” (Mark 14:35-36)

In spite of his personal feelings, Jesus submitted to the will of his Father. They were one in will and action but not one in personality.

What is the current understanding?

What we hold as Reformed Christians, according to the Westminster Confession of Faith, is that

In the unity of the Godhead there be three Persons of one substance, power, and eternity: God the Father, God the Son, and God the Holy Ghost. The Father is of none, neither begotten nor proceeding; the Son is eternally begotten of the Father, the Holy Ghost eternally proceeding from the Father and the Son.

This is based on the two passages,

Because you are his sons, God sent the Spirit of his Son into our hearts, the Spirit who calls out, “Abba, Father.” (Galatians 4:6)

When the Counselor comes, whom I will send to you from the Father—the Spirit of truth who goes out from the Father—he will testify about me. (John 15:26)

Does this clarify the situation?

How comfortable are we with admitting that there are things we don’t know? How comfortable can we be, living with what we don’t know? I don’t know the details of the way the persons of the trinity connect to each other. From the scripture I can find out the way they work together, but I haven’t got a clue about how it happens.

On the other hand, I don’t need to know exactly what goes on in the engine of my car in order to turn the key and drive down to the grocery store. I do need to know a whole lot about what the car will and won’t do, and I do need to know how to tell when things are broken. But I can live with my car without knowing all the details, and I can live with the trinity without needing to know more than I can understand.

In the old days, they used to call something we don’t understand a mystery, but these days a mystery is just another problem to be solved. The fact that we can’t understand God completely, shouldn’t be a problem for us. It’s just the way things are. After all, we’ve heard from the prophet Isaiah that God says,

“my thoughts are not your thoughts, neither are your ways my ways,” declares the LORD. “As the heavens are higher than the earth, so are my ways higher than your ways and my thoughts than your thoughts.” (Isaiah 55:8-9)

When Job challenges God,

the LORD answered Job out of the storm. … He said:“Where were you when I laid the earth’s foundation? Tell me, if you understand.” (Job 38:1,4)

Job wasn’t there, and I wasn’t either. I have to take God’s word for what happened, and if God sees fit to let me know the rest of the story later, that’s fine with me.

Where do we fit?

Our modern understanding of how the trinity works in practice is sometimes called the “communion” model of the trinity. Each of the three persons is truly a separate personality with intentions, ideas, feelings, and abilities that are uniquely their own. Each has a different way of interacting with human beings. But all three are deeply connected, interacting and cooperating with each other with a single purpose.

Jesus intended to include us, to include his people, in the kind of relationship that he had with the Father. At the last supper he said,

I will remain in the world no longer, but they are still in the world, and I am coming to you. Holy Father, protect them by the power of your name—the name you gave me—so that they may be one as we are one. (John 17:11)

This wasn’t just for the disciples, but also for those of us who come to him later.

You see, the kind of loving relationship that exists among the members of the trinity is the pattern that we should use for our relationship with God and with each other. Jesus says in his prayer,

My prayer is not for them alone. I pray also for those who will believe in me through their message, that all of them may be one, Father, just as you are in me and I am in you. May they also be in us so that the world may believe that you have sent me. I have given them the glory that you gave me, that they may be one as we are one: I in them and you in me. May they be brought to complete unity to let the world know that you sent me and have loved them even as you have loved me. (John 17:20-23)

The Father, Son, and Holy Spirit live in a continuous mutual sharing of love and intention, even though their individual roles and actions are different from each other. This is the way that the people of God should be living as individuals in one community, where we’re different from each other but joined in loving intention and commitment.

This kind of relationship—loving, supporting, and working together in different roles—is a model for the way we’re supposed to live together as the community of followers of Jesus. As the three persons of the trinity are one God, so are all of us who belong to Jesus one body. As each of the three is an independent person with different powers and different roles, so we’re each independent people with different gifts and different callings. As the three live together in one common purpose, so we’re to live together, growing closer to, and more like, the One who is our head.

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