It opens with the famous line: We are one, but we are many…

That sums up the noble dream of the song: that despite difference and diversity, there is in our land a deeper unity that we share.

It’s a dream that has haunted the modern world since the fall of the great empires. John Lennon imagined it in his anthem called, well, Imagine:

Imagine there’s no countries
It isn’t hard to do
Nothing to kill or die for
And no religion, too
Imagine all the people
Livin’ life in peace
You may say I’m a dreamer
But I’m not the only one
I hope someday you’ll join us
And the world will be as one.

It’s a noble ideal, but how can many be one? Particularly, in this Reconciliation Week, if we sing ‘we are one but we are many’ we are reminded that this is an unresolved tension for our nation.

You heard John Lennon’s solution: we can be one if we are a little less many. Dissolve the borders, be rid of religion, and, apparently, get everyone to sing sentimental songs. Be a little less local and a little more global. It’s a rock star’s solution.

We are one, but we are many: how? How can the many be as one, and still be the many?

Now, this is not an abstract question. It’s one that is right at the heart of what it means to be a human: how can I be properly me and yet live at peace with you? We need some kind of unity to live at peace with one another. Yet how can we find a peace that respects our difference, our individuality and freedom?

There are four main options that we are given to solve the one and the many problem: Power, Law, Values, and Money.

Option one is simple: Power. You just force everyone to be one. It’s no accident that this age of deep social divisions has made the rise of totalitarian regimes more and not less likely, despite what we know about them. Difference is so frustrating. And the imposition of order makes for a kind of peaceful living. But the cost is the violent suppression of the individual. We’re seeing this in countries as diverse as the Philippines, Belarus, and Hungary.

Option two is Law. You invent a constitution that will preserve unity and make space for difference. Democracy is the best system for this ever invented. But it has its weaknesses, too. Democracy, by definition, privileges the rule of the majority over the minority. That’s its only principle. As we’ve seen in the past two decades, democracies can be taken over by demagogues, or become gridlocked with disagreement.

Option 3 is Values. You can try to invent some universal values that a nation, or perhaps all people, can gather around. We used to say that certain behaviours were ‘unAustralian’, for example, as a way of saying that there was a certain universal culture to which all people should assimilate. An appeal to human rights operates in the same way. Now, I wouldn’t want to disparage how much good has been achieved by the idea of human rights. And yet the trouble is that values seem to shift with the fashions of the day. What one generation finds normal the next finds appalling. We keep discovering new human rights to add to the existing ones. So-called ‘universal’ values don’t seem that universal.

Option 4 is Money. What are we left with, then? Well, we can all agree, at least, that money is good and that we all want more of it, I suppose. Maybe, in the end, buying and selling stuff is what we most have in common with each other. We should just get the other stuff out of the way, because money is the only truly universal language. Of course, though we share the desire for money, we are also deeply and obviously divided by it.

Well, that’s all very interesting, you might say, but why have I been thinking about all this during the week of Trinity Sunday (May 30)? I’m glad you asked. Because it’s the doctrine of the Trinity that helps us precisely with this problem of the one and the many.

First, God is one. As you know, the Jews were and are passionate monotheists. The whole Bible tells us that the true God is singular and unequalled. There may be other claimants to divinity, but there is only one God, not many. And he is not divided into parts or personas. You don’t get an angry God on Monday and a gentle God on Tuesday. There is only one God, and he alone is God – this is what Israel learnt from the beginning.

But second, God is three. Remember, the New Testament writers also were passionate monotheists. But when they met Jesus after he had been raised from the dead they worshipped him as God. Even Thomas the doubter said ‘my Lord and my God’! Then when Jesus had ascended into heaven they received his Spirit – his presence with and among them. And they recognised that this Spirit, too, was God.

John Lennon was wrong: above us, in not only sky, it turns out: but love.

What is the secret of their unity? The Bible’s answer is as profound as it is simple.

It’s love.

God in three persons is a unity of perfect love. John puts it starkly in his letter, 1 John 4:16: God is love. That doesn’t mean that God is a vague, benevolent force. God is not the idea of love: we can say God is love because God actually loves. God is a set of loving relationships.

Father, Son, and Holy Spirit live together in relationship with one another, in what author Sam Allberry calls “a dynamic of love, of other-person-centredness”.

The best word to express this relationship is the Greek word koinonia, which means ‘communion’, or ‘fellowship’. God is a perfect koinonia. The persons of the Trinity belong to one another, and share in one another.

Let’s pause here for a moment and take in the view, gazing for a moment through the telescopic lens given to us by Scripture, at the very heavens.

The source of all things, from which they all came, from which they have their existence: that being is from eternity essentially and utterly love. You and I are made by a being whose entire disposition is to love. What we see when we gaze at the beauty and purpose of the world is an echo of the love which is in God. We are not made from the collision of the stars, nor do we emerge from the brutal struggle of our genes to survive and reproduce: we are made from the love of the Father for the Son. Love defines existence itself.

John Lennon was wrong: above us, in not only sky, it turns out – but love.

And, as Timothy Keller says: .“If this world was made by a triune God, relationships of love are what life is really all about.”

God is one. God is three. Three make one because of love. And that means life in God’s world is not directed towards survival or acquisition or individual fulfillment in expression, but towards love.

The purpose of your life, and mine, is to love. The secret of human unity is found in loving one another.

But how does that help us?

Particularly when you register anew the reality that we human beings do not love as we are called to love. That’s where we began: love does not mark humankind, and so humankind is not united.

Just telling us to love more is a nice message, but not perhaps any more helpful than John Lennon, or the words from I am Australian.

But the God who is love is better than John Lennon.

To take one New Testament example: you can see how the logic of this works in Paul’s letter to the Ephesians. You might remember that Ephesians is a letter addressing the issue of ethnic diversity in the church. How can Jews and Greeks live together as Christians? They have different foods, different customs, different habits. How could it work?

But Paul says, in Ephesians 2: What unites you together is the cross of Jesus Christ. From love, he died for the sins of both Jews and Greeks. He’s made one new humanity out of the two, by the blood of Jesus Christ, who is our peace. He’s healed the rift between them by healing the rift between them and God.

How can the church of the triune God live as one while it is many? Because we are going to pursue humility, gentleness, patience and love.

It’s no surprise then, that God would call them as his people to practice living in loving unity with one another, since he himself has made them one (as Paul explains in Ephesians 4). By the one faith and the one baptism into the name of the one Lord they have become one body sharing one Spirit and are children of the one Father.

The church of Jesus Christ is to be an echo of the God who has saved it. You and I not are divine beings and cannot love as they love, in perfect communion. And yet, the love of God dwells in us and empowers us to love one another.

If you’ve ever sat in the gallery of my church when one of our organists really chooses to let it rip, you’ll realise that the bass pipes are up there. And when those bass notes go, the whole building and your whole body resonate with the sound of that mighty blast of sound. You more feel it than hear it.

We are called to reverberate with the love of God – to let its power shake us to the core, so that it is amplified in us. As theologian Colin Gunton explains, we are called to be the kind of reality in finite terms that God is in eternity.

And this is a very practical truth. You can see what Paul does with it in Ephesians 4. What is it to look like? We are to make every effort to maintain the unity of the Spirit in the bond of peace he says. How? It’s in verse 2 – humility, gentleness, patience, bearing with one another in love.

How can the church of the triune God live as one while it is many? Because we are going to pursue humility, gentleness, patience and love.

Let me focus on just one of these: humility. The love of God is humble: it gives itself to the good and the glory of the other.

Are you pursuing a true and Christ-like humility? This means never being too good for any task. You may be, in the world’s terms, greatly honoured. You may be used to people running around after you. But in the church: are you a servant? And how do you treat those who serve you? We are far too used to paying people to do the supposedly menial things that need doing. Yet these things are an opportunity for us to echo the love of God. I suspect that this reflects a lack of humility among us. We too easily reflect the culture which says that important people are too busy for ordinary things.

And yet: it is in acts of humble, loving service that the love of the triune God is found to be in us. This is the shape that the love of God should take among his people. His love vibrates through his people so that people see what it is like and know that we belong to him. We live out together our profound unity because we have been formed by the God whose unity consists of love.

And when we resonate with the love of God, when we practice it, then we can show the world the way that we can be one, and many, at peace.

Is that too grandiose? It’s happened before. In his great recent book Dominion, English historian Tom Holland shows that it was Christianity, proclaiming that God is love, that provided the basis for our contemporary ideas of justice, freedom, equality, and human rights. Though John Lennon was an atheist, he could not have imagined his world at peace without Christian ideas ringing in his ears. His contemporary, Martin Luther King, saw his commitment to civil rights for African Americans as a biblical imperative stemming from the love of God.

So, let us begin with those people that the three-personed God who is love has given us to love – and who knows what he may do?

Michael Jensen is the rector of St Mark’s Anglican Church in Darling Point, Sydney, and the author of several books.