Sermon preached at the Sung Eucharist on Trinity Sunday 2026

In the name of the Father,

And of the Son,

And of the Holy Spirit…

Amen.

I wonder how many of you crossed yourself somewhat absentmindedly as I invoked the name of the Trinity? In the name of the Father, and of the Son and of the Holy Spirit… Some version of those words appears over and over again in our worship, girding all our prayers and praises about with reminders of the doctrine that stands as a central pillar of the Christian faith – from which so much flows – the Doctrine of the Trinity that we particularly celebrate this Trinity Sunday. We hear about the Trinity all the time: in phrases like the one that began this service, this sermon, in our creeds, in the praises at the end of psalms or canticles, when we bless, when we break bread, when we baptise, marry, or are buried, all are done in the name of the Trinity. And yet, the Trinity is so difficult to talk about without falling either into heresy or feeling like we have stumbled into some kind of strange paradox. God is three persons, yet one substance, one in Godhead, the Majesty co-eternal, and yet they are not three Gods; but one God – to quote the Athanasian Creed. It’s difficult to talk about without drifting into either very vague analogies or very contested and specific theological terminology – either fluffy and ungraspable, or confined to dusty tomes in a theologian’s study. We are told over and again that it is a mystery that we must enter into, something we can never fully grasp, and that isn’t just a preacher’s cop-out, but a very real statement about the impossibility of the finite human mind grasping the infinity of God. And yet, for all its complexities, without the Trinity, our salvation doesn’t “work.” We are Christians because of the Trinity; all we believe about Jesus is because of the Trinity. It is not something “over there” to be glanced at sideways before we look away. It is the heart of things. But one of the difficulties of the doctrine of the Trinity is that it seems so impractical. All the talk about mystery, a vague sense that you have to be clever, or to have read a lot of books to understand it, threatens to make the doctrine of the Trinity feel so removed from our actual lives and how we live them. Theologian Elizabeth Johnson once said that, if people read in their newspapers one morning (revealing something of when she was writing) that an extra member of the Trinity had been “found,” most people just wouldn’t care. What practical difference would it make?

In true sermonising form, I am going to answer that question by asking another: How do we even know about the Trinity? How do we know that is what God is like? One way, of course, is through scripture. Our readings this morning contain a few of the mentions of God as Trinity: We have the fantastic Gospel from the end of Matthew, which sums up all of Jesus’s ministry and tells the disciples (and us) what to do next, including baptising people in the name of the Father, Son and Holy Spirit. We have the reading from 2 Corinthians, which gives us “The Grace”, which we use at the end of some services to remind us in whose name we do what we do. We might be able to think of more examples: Jesus’ baptism, for instance, with the voice of the Father, and the Spirit descending upon him as a dove, or the Annunciation, where the Holy Spirit will come upon the Blessed Virgin Mary, and the power of the Most High will overshadow her so that the child to be born will be called the Son of

God. It’s also important to remember that the Son and the Holy Spirit don’t just “appear” in the First Century AD, entirely present only in the New Testament. The Spirit hovered over the face of the waters at creation, and wisdom – the logos, the Son, the Second Person of the Trinity – was also there at the beginning of all things.

Scripture underpins our faith, but the other crucial way that we know about God is through experience. We might not all have a “thunderbolt” instance of knowing God’s presence, but perhaps as a gentle pressure through our lives, through the lives and witness of others, or something still deeply longed for. Our experience of God, whether we consciously know it or not, is deeply Trinitarian. It might perhaps best be summed up in the formula you might recognise as one often used at the beginning of intercessions: “in the power of the Spirit, and in union with Christ, let us pray to the Father.” So, we’re praying to the Father, the creator, the source of all being. What allows us to do that, what allows us to call him Father at all, is our relationship with Jesus Christ, the second person of the Trinity. Jesus’s incarnation, death, resurrection and ascension have allowed us to have a new relationship with God, one in which we are also children of God and fellow-heirs with Christ. This allows us to address him in that familiar form: “Our Father.” Our prayer is enabled by the incarnation. You may spot other examples of that formulation during this Eucharist. At the end of the Eucharistic prayer, for example: “Through Jesus Christ our Lord; by whom, and with whom, and in whom, in the unity of the Holy Spirit, all honour and glory be yours, almighty Father, for ever and ever. Amen”

We can turn to the letter to the Romans for some explanation of this. St Paul writes: ‘When we cry, ‘Abba! Father!’ it is that very Spirit bearing witness with our Spirit that we are children of God, and if children, then heirs, heirs of God and joint heirs with Christ.’ In this segment from Paul, we have a glimpse of the Spirit’s role in all of this. The Spirit, dwelling in us, is the one that bears witness to us and for us. The one we actually touch when we experience God, and through whom we experience Father and Son. It’s genuinely really difficult to articulate. It’s like the Spirit is the postman who carries our prayer to the Father, and the Son is the one who sticks the stamp on the envelope. Or the Spirit within us is a chord, stretched tight between us and the other members of the Trinity, and when we pluck it, it hums in harmony with the eternal music that is the love that overflows the triune Godhead. I’m sure my clerical colleagues are twitching at those metaphors, but with the mystery of the Trinity, back to metaphors we always must turn, acknowledging that they can only ever tell a part of the story. So, when we pray, or when we have any experience of God, it is through the power of the Spirit, and in union with Christ and directed at the Father.

So, what practical difference does the doctrine of the Trinity make? The Trinity is how we experience God. All our prayer, all our worship, all those moments when we know that God is present are in the power of the Holy Spirit, and in union with Christ. It is Christ that enables us to know God differently, enables us to be children of God, and to have God’s presence with us. It is the sending of the Holy Spirit at Pentecost that gives us the power to know that presence to move in it and to keep us in contact with the loving life of the Trinity. It is a mystery, but a mystery into which we are invited, in which we know ourselves as children, in that we are enabled to know God as Father. So, this Trinity Sunday, May the grace of our Lord Jesus Christ, the love of God, and the fellowship of the Holy Spirit be with us all, evermore.