For many years Trinity Sunday has coincided with my annual holidays, but this year there was a calendar malfunction. Fortunately, earlier in the year something caught my eye in a blog about Christian contemplation, written by a Fanciscan priest called Richard Rohr.
He was reminiscing about his childhood when, he recalled, priests used to tell him and his friends that the Trinity is a mystery, something so difficult to comprehend that we shouldn’t even try to understand it. I remember being told exactly the same thing, and it always seemed peculiar to me that we should be encouraged to believe in something which we couldn’t get our heads around. How can we really be expected to believe in something even if it’s a total mystery?
The solution, as Richard Rohr observes in his blog, is that on every other day of the year most Christians get around the problem by behaving as though the Trinity doesn’t exist. Quoting the famous theologian Karl Rahner he says that, if the Churches all agreed to give up the doctrine of the Trinity tomorrow, nine-tenths of everything ever written about the Christian faith wouldn’t need to be altered at all.  Even our Gospel reading from John 16, verses 1 to 5, doesn’t try to describe the mechanics behind the Trinity. John only implies that there is a moral unity between Father, Son and Spirit.
But ignoring the Trinity because it’s too difficult to think about certainly won’t work on Trinity Sunday. In any case, Richard Rohr says he’s come to realise that divine mystery isn’t something we can never understand, it’s something we can endlessly understand, because it has so many meanings that we can go on exploring it forever.
So, for instance, he suggests that one way of thinking ourselves into the meaning of the Trinity is to use the metaphor of dance. I asked everyone at the 9.30 service whether they like dancing - perhaps at weddings - or at least like watching Strictly Come Dancing or Dancing on Ice? Or I asked, what about ballet? Even the presenter of BBC Radio’s culture programme admitted on air last week that to him ballet was a mystery. He’d never understood it or even sat through a whole ballet performance. Of course, there was an expert on hand from the National Ballet to complete his education for him!
Richard Rohr says that God doesn’t just enjoy dancing, God isn’t just one of the dancers in the dance of creation, God is the dance itself.
He suggests that we think about the building blocks of life and the universe. They’re all made up of smaller particles or life forms bound together or moving around one another.
In the atom there’s a lot of hugging and dancing going on. Here protons and neutrons hold onto each other in a tight embrace in the nucleus of the atom while electrons dance around them, although I think it’s a bit more complicated than that.
In the tiny cells that make up all living things there’s an ancient life form lurking, called mitochondria, which you can see dancing around inside the cell giving it energy. The mitochondria themselves are constantly bonding and separating as they dance around inside the cell, where they have a symbiotic relationship with the creatures they inhabit. We can’t live without them, and the energy they help us to burn, but they can’t exist without us.
On a much bigger scale, the moon orbits the earth with its waxing and waning face in a constant dance of high tides and low tides. And, on an even larger scale still, the planets orbit the sun and stars dance around one another in galaxies, sometimes with slender arms spiralling out into deep space.
Richard Rohr says that the Trinity is ‘embedded as the code [which is] in everything that exists.’ The Trinity is engaged in ‘a circle dance of love’, so is it any wonder - he asks - that people and animals, birds and fish, move and swirl in complicated patterns too - shoals, flocks, herds, packs, social groups and families, not to mention children in music and movement classes, all dancing and sometimes tip-toeing around one another?
And God is the dance itself. And God wants us to join in the dance, to dance with one another and with him. And it doesn’t matter if we’re notorious Dad dancers, or we have two left feet. We are all invited to get on the dance floor!
Speaking of which, in 1990 the Methodist Church - in a report to Conference about human sexuality - compared the Trinity to the relationship between two people. When we attempt to describe the unity within the Trinity we talk about three persons being in such complete unity that they are one and the same, and the report said that human relationships can be something like that - with two marriage partners becoming united together in the Spirit.
Jesus himself said that when two people get married the two should become one. Of course, he wasn talking about the perfect unity that exists between the three persons of the Trinity but the report said that, in sexual intercourse, human beings come as close to experiencing what it means for two persons to become one as most of us are ever likely to get. When I mentioned this in a sermon at the time, a church steward commented wryly that it was the best excuse he had ever heard - but I don’t make this stuff up.
According to the report sex - at its best - really does become a way of better understanding the mystery of God, of joining in the dance at the heart of all creation. It says, and I quote, ‘The Trinity [is] an expression of the outgoing love of God in creation, re-creation and [personal] relationships… Therefore, sex is to be enjoyed and celebrated within this context... We celebrate our sexuality because we have been made by God with the potential to be fulfilled in deep loving relationships and... [so can] be at one with another person.’ And it also says, ‘A secure, intimate, stable, loving bond, [between two people] is itself a reflection of the mystery of the relationship within the Trinity.’ 
So it’s fitting that today. on Trinity Sunday itself, we will be marking and celebrating the renewal of two people’s vows to one another after fifty years of Christian marriage.
 The Report of the Conference Commission on Human Sexuality, 1990