Jews, Christians and Muslims all believe in One God. The prayer most often recited by Jews begins: 'Hear, O Israel: the Lord our God, the Lord is One'. The Creed proclaimed by Christians begins: 'We believe in One God'. And Muslims constantly repeat: 'There is no god but God'.
But Christians also say something else about God. The Christian faith teaches that God is Three-in-One, a Tri-Unity or Trinity. The Creed begins 'We believe in One God', but goes on to speak first of God the Father, then of God the Son and then of God the Holy Spirit. This threefoldness in God is the focus of our worship and thinking today, Trinity Sunday.
It may surprise you that the word 'Trinity' does not occur in the Bible and that there was a long, complex process before the early Church agreed the doctrine of the Trinity. To Jews and Muslims, this suggests that the idea of the Trinity is a departure from true belief in One God. And of course for atheists it is an elaborate dressing-up of the basic error of believing in God at all. But Christians have continued over the centuries to teach that God is indeed Three-in-One and that this is not a fanciful idea we have dreamt up, but a profound truth that God has led us to recognise: a wonderful discovery, not a bizarre invention.
So why do Christians believe that God is Three-in-One, and why does it matter?
Christians did not start to call God 'Trinity' because they were bored of the old way of talking about God and wanted to jazz it up with something a bit different, a bit of mystery and paradox. The earliest Christians were all Jews and took it for granted that there is only one God. But they had to make sense of their belief in the One God in light of the new thing that they had experienced: that the One God, the Creator, had now come to them in the flesh in the human being Jesus of Nazareth, and then through the sending of the Holy Spirit. It was not that God had never communicated before; through Moses and many other prophets God had spoken to Israel. But with Jesus and the Holy Spirit something quite new had happened; God had not just sent a messenger but had come in person. In the sending of Jesus and of the Spirit God had given himself; God had become present in the world in a new way.
A common response to this is to say: well, maybe we are talking here of different aspects of the one God, different faces God shows the world, but underneath these different aspects God remains fundamentally One. Think of the complexity of being a human being in relation to different people. To my wife I am husband; to my children I am Father; to my colleagues I am a colleague. But I am one person not three. Is that what the doctrine of the Trinity is saying: that there are three key ways God has related to the world, but that underneath there is just the One undifferentiated God, just as I am one person underneath my different roles?
No, the doctrine of the Trinity is not saying that. It's not saying that God has revealed himself successively as Father, Son and Spirit (but underneath is just One). It's saying that in this new presence of God in the world through Jesus and the Spirit the disciples see into the very heart of God, the very life of God; and they see there the loving relationship of distinct persons: the love that goes between the Father and the Son through the Spirit, constantly outpoured, constantly received. While I may unite within myself husband, father, colleague and many other roles, these are not distinct persons in relationship with each other. But the being of God is different from ours, far richer than anything we can imagine, and within the being of God there is the relationship in love of the distinct divine persons, Father, Son and Spirit.
It's worth reflecting here on the famous and very simple words from the First Letter of John: 'God is love'. What do we mean when we say that God is love? This is a lot more than saying that God is loving. We might all hope that, at least on our better days, we are loving people. Take your name and put it before the words 'is loving': 'John is loving'; 'Mary is loving'. True at least some of the time, we hope. But put your name before the words: 'is love': 'John is love'; 'Mary is love'. That's not so easy; in fact it doesn't make sense. But we can say 'God is love' and that's not just because God is more loving than we are. The point is that love is about relationship. Where there is no relationship there is no love. For there to be love, there must be both one to give love and one to receive love. Love goes between persons. That is why I cannot say of myself 'I am love'. On my own, I am not love, although in relationship to others I can give and receive love.
But what cannot be true of you or me as individuals is true of God, because God is love. God is not just very loving towards other beings. God is actually love within God's very self; God is a relationship of love within God's very self. Within God there is a giving and receiving of love. This flow of love is between the persons we call the Father, the Son and the Holy Spirit. This flow of love within God has always been there. It is the origin of everything that is. Everything else that is comes from the love that God has always been.
This truth was not revealed – bang! – in one go to the disciples. Jesus did not sit them down and explain the doctrine of the Trinity to them on the first day he called them. But this underlying reality of what God is – the eternal loving unity of Father, Son and Spirit – was present in all that Jesus was, said, and did and in all that the Spirit did in and through the disciples. Think of the baptism of Jesus, when the Holy Spirit descends upon him and the Father declares from heaven: 'This is my beloved Son.' That is the eternal Trinity, breaking out into this world as the story of Jesus gets under way. And so it went on.
So from earliest days Christians spoke of God the Father; Jesus, God's Son; and the Holy Spirit of God; and they baptized new disciples in the name of the One God, Father, Son and Spirit. You will not find the word 'Trinity' in today's readings from 2 Corinthians and Matthew, but in both of them and in many other passages we see an emerging pattern of threefoldness in the way God is described. And, gradually, Christian teachers developed the language of the Trinity, the eternal threefoldness in unity of God, to describe the revelation and the experience of God found in the New Testament.
That was an attempt to explain how Christians came to believe that God is Trinity. But so what? Why does it matter?
The doctrine of the Trinity matters because it tells us that the source and bedrock of all reality is love, divine love and we are invited to live out of that love. Before anything else was, there was divine love. Everything else flows from that creative love. That love is still the bedrock of reality, holding all things together. And it always will be. That may of course be very hard to believe at times, both because of the awful things that happen in the world and the painful things that we experience and which make us question whether there is any kind of God at all, let alone a God of perfect, eternal love. But the love that God is is the love we see in Jesus, a love that heals and makes new, that restores and forgives, a love that embraces suffering and is with us in all things. But not a love that zaps the world into order and ends its chaos with a simple command. That is not the kind of divine love that was revealed in Jesus.
The love of God the Trinity is a love that constantly opens itself up to us, drawing us into the same dynamic of giving and receiving love. God sent Jesus and the Spirit to open up to the world the circle of divine love and to call us to receive that love and learn to give it. And just as God's sending of Jesus involved suffering, as we are drawn into the circle of divine love we too will share in something of that suffering, because suffering is the cost of love in this world. As we know, this world is full of pain and sickness, misery and heartbreak, injustice and violence. In this world the path of love – the kind of love we see in Jesus – is a path of suffering, but if we follow this path in the company of Jesus and in the fellowship of God's Spirit, it is also the path on which we will know the glory of God, who by raising Jesus from the dead has promised to make us and all things new in him.
So today we celebrate God the Holy Trinity. This ancient but ever new doctrine teaches us to open ourselves up to the God who as Father, Son and Spirit is eternal love and draws us into that love, to know its glory and also to accept the pain that comes with loving. We are called to live that love in our homes, in the fellowship of the Church and in ever wider circles in the world, wherever the love of God draws us.
Thank God, there is so much of that love already at work here at St Ursula's in many different ways, rich and costly love, reflecting the love of the God we worship, the God who is love. But that love is a restless, creative power always calling us to go further. So we pray that the love of God the Holy Trinity, Father, Son and Spirit, will be poured out on us: on us who often struggle to know what love means, who sometimes want to keep love at arm's length, who constantly fail to love as we should. We pray that we will be drawn deeper into the love which was before all things, which is today, and which will be forever.
Amen
Revd David Marshall