I. Introduction: why we need this

A. Stating the topic

We say that we have a “Trinitarian theology.”  However, most churches accept the doctrine of the Trinity, and their theology is at least some­what Trinitarian, but we emphasize the Trinity more than most churches do. Sometimes we say that we have an Incarnational Trinitarian theo­logy, or a Trinitarian Christ-centered theology.  None of these are completely distinctive terms, but they do mention some of the emphases that we have.

We call our theology Trinitarian because the doctrine of the Trinity is not a side point, or just one of many other doctrines.  We are trying to be more consistent with it, to let it be the organizing principle for other doctrines.  Whether we are talking about sin or salvation or the church, we want to ask, how does the doctrine of the Trinity help us understand this particular doctrine?  How is it connected with the nature of God, and of who God is in his innermost being?

We are trying to understand a little better some points about God’s relationship with humanity: his purpose in creating humanity, the way in which he saves us, and how we should respond to him.  We believe that our theology is true to the Bible, and that it helps make sense of what we are doing on the earth and in the church.  It helps tie different doctrines together.

B. Not trying to criticize others

In the process of explaining our theology, we find that our beliefs are sometimes a little different from other theological traditions, and in some points of doctrine, we conclude that those other Christians are mistaken.  This does not mean that we think they are non-Christian, or that those people won’t be saved.  We all make mistakes, and we have no doubt made a few of our own.

We all believe that we are saved through the life, death and resurrection of Jesus – and it is good for us to have that in common with many other Christians around the world.

Thankfully, we are saved not by having absolutely perfect theology, but we are saved by Christ, by grace, by trusting in Jesus to do for us what we cannot do for ourselves.  Other Christians are doing the best they can, and we are doing the best that we can, to understand the Bible, and to understand the meaning of life and how it all fits together.  Our purpose here is not to criticize other people and other theologies, but simply to do the best that we can in explaining what we believe, and how we think it is true to the Bible, and how we think it helps us understand what our life is all about.

C. A desire to understand as much as we can

This is what the early church called “faith seeking understanding.”  We already understand some things about God, and we believe them, but we are convinced that this is something we’d like to know more about, and so we try to understand as much as we can.  We have fallen in love with Jesus, and we’d like to learn more about who he is, and the relationship he has with us, and what he has in mind for our future.

We could also describe our goal as an act of worship: we want to praise God for who he is and what he has done and what he has promised to do in the future – and in order to praise God for these things, we need to understand what they are.  The goal is to explain things as best as we can, based on the Bible and the way that God has revealed himself to us ultimately and personally in Jesus Christ.

D. Practical significance

We will not try to cover all the biblical or historical evidence for the doctrine of the Trinity.  We have published other articles about that.  What we would like to focus on here is the practical significance of the doctrine.

At first, it seems like the doctrine of the Trinity is just information about God: God is three Persons in one Being.  It’s about him.  But what does that have to do with us?  Does it make any difference to us here on earth?

Yes.  That is because persons have relationships with one another, and relationships are important for all of us.  God created us to have relationships similar to the relationships that exist for all eternity within the Triune God. The divine Persons in the Godhead have relationships, and persons here on earth have relationships, too, and there is supposed to be some similarity in the kind of relationships we have.

The Bible tells us that “God is love” (1 John 4:8).  Not that he has love, but that he IS love.  That is descriptive of who he is and how he lives in eternity, how he interacts with other persons.  Even before God created the universe, even before God created angelic beings, he was love.  When God was the only thing there is, God was love — love among the triune Persons.

Before God created anything, what would God be like?  If there is only one person in God, there would be no one to love, because love means caring for and caring about someone else.  But if God were somehow loving but alone, that would mean that God would be unable to fully be or express some of his internal nature.  God would be deficient.  The statement that “God is love” would be meaningless before creation, if God were only one Person, because the love could not be expressed.

The doctrine of the Trinity tells us that even before God created anything, he could be love, because the Father loved the Son, and the Son loved the Holy Spirit, and the Spirit loves the Father, and so forth.  There was love within the Triune God, even before anything had been created (John 17:24).  The three Persons were distinguishable from one another, but united to one another in love.  This is important for who God is, and it’s important for who we are, as well.

II. Centered on Jesus Christ

As mentioned above, we sometimes say that we have a Trinitarian, Christ-centered theology.  Some people wonder, if all three Persons in the Godhead are fully divine, and equal in being divine, why should we center our theology on one of them in particular?

A. Jesus is fully divine

God is revealed to us most clearly in the Person of Jesus Christ.  Jesus is where God has chosen to make himself visible to us (Colossians 1:15).  Jesus is the Word made flesh — God the Son become human.  He has revealed himself in a way that we could see him, touch him, hear him and see how he lives.  Jesus is the way that God has chosen to reveal himself to us.

In John 14:8, Philip asked Jesus: “Lord, show us the Father and that will be enough for us.”  Jesus responded in verse 9: “Don’t you know me, Philip, even after I have been among you such a long time?  Anyone who has seen me has seen the Father.”

Jesus is not saying that God the Father is 5 foot 8 inches tall, with brown hair and Middle Eastern features. Rather, he is saying that in his most important respects (his character, purposes, heart, and mind), God the Father is like Jesus Christ in terms of the way he interacts with others.  The compassion that Jesus had shows us what God is like.  The zeal for righteousness, that’s what God is like.  The willingness to sacrifice for others, God is like that, too.  Jesus helps us see what God the Father is like – and the Holy Spirit is like that, too.

When Jesus became a flesh-and-blood human being, he was showing us in a tangible and visible way what the Triune God is like.  The apostle Paul says, “The Son is the image of the invisible God” (Colossians 1:15).  Even though we cannot see God directly, Jesus shows us what he’s like, in a way that we can see and hear.

Colossians 2:9 says, “In Christ all the fullness of the Deity lives in bodily form.”  Jesus is the summary that we are given of what we need to know about God.  We can never know God completely – he is much bigger than our minds are capable of comprehending – but we are able to have an accurate understanding of at least some things about God, because Jesus embodies all that any human being can know of God, and he came to reveal God to us.  He does not reveal everything, but what he does reveal is accurate.  John 1:18 says, “No one has ever seen God, but the one and only Son, who is himself God and is in closest relationship with the Father, has made him known.”

B. Jesus is fully human

All orthodox Christian theology includes the teaching that Jesus is fully human.  That might seem obvious to many people – he was born as a baby, grew as a boy, and he died.  As the Bible says, in John 1:14, “The Word became flesh and made his dwelling among us.”  He didn’t just put on a costume that made him look  human – no, he was a real human being.  He ate ordinary food, breathed air like an ordinary person, his fingernails grew and he got thirsty and tired. When he scraped his knee, he bled, and when they crucified him, he died just like other people would have.

He was fully God and fully human – both at the same time.  We have never seen that combination before, but with God, all things are possible, and so if that’s what he did, then we have to make room in our theology for it.  God can do one-of-a-kind things that aren’t comparable to anything else.  He is able to be in his own creation.  The Incarnation of the Son of God is that unique kind of thing.

There are a number of reasons as to why a divine Person might want to become a human being. He came to communicate to us on a level we could understand; he came to die for us; he came to experience life as a human so that we could know for sure that he understood what it’s like for us to be human. But just as Jesus shows us what God is like, he also shows us what humanity is really like. He is the perfect human.

C. Connecting human beings to God

Jesus has a unique role.  He has been part of the circle of God’s triune life, and he’s been part of the human circle of life, and because of that, he provides a unique connection between humanity and God.  In a sense, he is a bridge between the two, a bridge God uses to bring us into the divine fellowship.  Not that we are part of the Trinity, but in and through his humanity, we do share in God’s life.

2 Peter 1:4 says, “He has given us his very great and precious promises, so that through them you may participate in the divine nature.”  So in some way we participate in what God is.  We are in the family of God, or the kingdom of God.  We are in fellowship with God, in a relationship with God – and this is all made possible by Jesus.

1 Timothy 2:5 says, “There is one God and one mediator between God and mankind, the man Christ Jesus.”  A mediator is a person in the middle – in this case, a person serving to connect humanity with God.  God initiated this; he is the one who sent Jesus to earth to become a human being, and to be resurrected back into heaven to make this connection work.  Jesus is the key link or connector between humanity and God.

The doctrine of the Trinity is important for this understanding.  For our connection with God, for our future with God, it is essential that our mediator be fully God in his own right.  No human being is good enough to earn a connection with God, who is infinitely far above us in power, glory, wisdom and righteousness.  No created human being could rise up to God’s level as Creator, but God is able to put himself at our level.

Jesus is perfect in righteousness and holiness, and yet one of us.  He is the pathway by which other human beings are brought into the presence of the holy and perfect God.  The doctrine of the Trinity says that Jesus is fully God, and the doctrine of the Incarnation says that Jesus became fully human, and he continues to be both divine and human, and with that combination, now we are ready to talk about a relationship between God and humanity.

III.  Humanity in the image of God

A. Created in his image

Jesus shows us what God is like, and he also shows us what humanity is supposed to be like, and this implies that there is some important similarity between God and humans.  This is not because humans are good enough to rise up to the level of God.   No, it all comes from God as a gift given to us.  He is the one who created us this way in the first place.  We find it stated in the first chapter of the Bible:

God said, “Let us make mankind in our image, in our likeness, so that they may rule over the fish in the sea and the birds in the sky, over the livestock and all the wild animals, and over all the creatures that move along the ground.” ²⁷ So God created mankind in his own image, in the image of God he created them; male and female he created them. (Genesis 1:26-27)

God did it, and he said it was good.  Humanity was created “in the image of God,” to somehow look like God and to represent God here on earth.  Again, we are not supposed to think of skin color, hair color or the number of fingers on our hands.  Those things are incidentals that only apply to creatures.  What is important is that humanity should be like God in a spiritual sense, and we see that emphasis in Galatians 5:22, where the apostle Paul describes the results of the working of the Holy Spirit in us: “love, joy, peace, forbearance, kindness, goodness, faithfulness, gentleness and self-control.”  Humans are supposed to be like God in these ways.

Now we can ask the Trinitarian question: In what way does the doctrine of the Trinity help us understand what humanity is?  The answer is, that just as the Persons in the Trinity interact with one another in love, so also we as persons ought to interact with all other human persons in love. That’s the first fruit of the Spirit, and the way that we were made to be like God.  Love should be the basis for our lives and our societies.

Just as the Triune God is essentially relational, with the Persons defined in reference to one another, so humans are also essentially relational, and our identity as persons depends on our relationships with other people.  “Who we are” depends on the relationships we have with others.  No one is a solitary individual; the meaning of life is not in self-existence, but it is to be found in our relationships with each other, in the way we live and think about other people.  We were created to be in right relationship with the Triune God and also to be in right relationship with each other in a way that mirrors Jesus’ relationship with the Father and the Spirit.

B. Sin defaces the image

Genesis tells us that humans didn’t want life on the terms that God had given them.  They wanted to define their own life, doing their own thing, instead of having to do God’s things.  So instead of love, joy and peace, they choose selfishness, and they got strife and unhappiness.

What does the doctrine of the Trinity reveal about the nature of sin?   How does it help us better understand what sin is?   If good is defined as humanity being in the image of God, then sin is doing things that are unlike God.  If God is a relational being, and humans were created to be in relationships of love, then sin is a disruption in our relationships – problems in our relationships with God, and problems in our relationships with one another.

As a practical matter, we have rules that describe what a good relationship is.  In a good relationship, we don’t lie to each other, we don’t steal from one another, we don’t dishonor or disrespect the other, and so forth.  Avoiding these problems doesn’t necessarily create a good relationship, but breaking these rules hurts our relationships.  Rules do not exist for their own sake, but in order to serve something more important, and that is relationships based on love.

When humanity rejected God, we also rejected him as the source of the love that we need.  We were created to be like God in that respect, but we went in a wrong direction.

C. God restores the image – in himself

The Old Testament doesn’t say much more about the image of God, but the New Testament picks up the phrase “image of God” and applies it to Jesus Christ.  We have already looked at Colossians 1:15: “He is the image of the invisible God.”  He is the image that Adam failed to be.  He shows us in a visible way what God is like in the invisible, spiritual world.

Hebrews 1:3 tells us something similar: “The Son is the radiance of God’s glory and the exact representation of his being.”  When we see Jesus, we see what the Father is like in relationship to Jesus.  So we expect God to be like Jesus, in his compassion and mercy and love.

D. We are in the image of Christ

This concept becomes directly relevant to us when we see that the Bible talks about us being formed in the image of Christ.  We can see this in 2 Corinthians 3:18: “We, who with unveiled faces all reflect the Lord’s glory, are being transformed into his likeness with ever-increasing glory, which comes from the Lord, who is the Spirit.”  That is, we look more and more like him – and again, that’s not talking about his physical shape, size and color – it’s talking about the way he is spiritually, in relationship to the Father and the Spirit from all eternity.

• Galatians 4:19 talks about how “Christ is formed in you.”
• Ephesians 4:13 talks about how “we all reach unity in the faith and in the knowledge of the Son of God and become mature, attaining to the whole measure of the fullness of Christ.”  
• Colossians 3:10 says we “have put on the new self, which is being renewed in knowledge in the image of its Creator” – and that is Jesus Christ.

Since Christ is the image of God, when we become more like Christ, we are being brought back toward the image of God that we are supposed to be.  Right now, it is a spiritual transformation, a mental and ethical or relational transformation, and eventually, it will be a physical transformation as well, all based on God’s original plan.

This concept is seen in a different way in Romans 5.   In that chapter, Paul is comparing Adam with Jesus Christ.  Romans 5:14 says that Adam was a type, or a model, “a pattern of the one to come.”   Just as the first Adam brought in sin and death, the second Adam brought in righteousness and life.  Just as we shared in the results of the first Adam, so also we share in the benefits of the second Adam.  Paul summarizes it in Romans 5:18-19:

Just as one trespass [Adam’s sin] resulted in condemnation for all people, so also one righteous act [that of Jesus] resulted in justification and life for all people. For just as through the disobedience of the one man [Adam] the many were made sinners, so also through the obedience of the one man [Jesus] the many will be made righteous.

ALL humanity was included in the results of the first Adam, and ALL humanity is included in the results of the second Adam, Jesus.  It’s not just a few people that God chose ahead of time, and it’s not just one particular nation, or one particular social class – God’s plan is for everyone he has created.   Jesus is Lord of ALL.

Adam messed it up, but Jesus did it right — and in Christ, all humanity has a fresh start on being “the image of God.”  Jesus is the key to our transformation – not only is he the model that we copy, but he is also the engine that drives the whole process.  He supplies the power and the direction.