GOOD afternoon, ladies and gentlemen. Thank you for coming to my exhibition. Please do understand, I'm a painter, not a talker. I have allowed myself to be persuaded to talk about this one work, on the easel here.

After a lifetime of painting ragged mountains, storms, dilapidated farmhouses, detached huts, shadows, how to talk about what at least began as a crowd scene? I shall try to take you through from that painting to what you see here. Not obvious, now, why it's called Jesus in Gethsemane. OK, Jesus with his disciples was in a place people called Gethsemane.

Here, look: olive trees, and, between them, some steps down - not far down, but into some seclusion; small stone steps, dandelions, you see, bluebells. My Gethsemane is a space left over from wartime bombs; a church was bombed near where I have my studio, hardly a trace of the building now, some steps, the single arch of a doorway, a yew tree, a few gravestones, the rest gone.

The bomb carved out a crater, about which more later. And you see, if you look here, one part of the garden, and another, where Jesus went after he'd said: "Wait here, I am going over there to pray." He didn't go alone, it says that he took Peter, and the two sons of Zebedee along with him, and it says that he began to be sad and troubled.

I hope that you can see how I tried to ease that moment into the present tense, make it present, show him being troubled and sad. If you look here, imagine him on a bright evening going into a bleak aura of darkness - I don't have the words, sorry - a darkness all of his own. He allowed it, welcomed it even, to allow resolution of it somehow, poor man. And there is a greyer shadow where the three disciples were, unable to keep still: you see a shivering grey.

IMAGINE what it must have been like for them to hear him say: "My soul is submerged into such sadness it is like dying." To indicate these words, I painted a splutter of light - not a splutter, I don't know, sorry - where he says as well: "Stay here and help me to wait and wait." This made me straighten the disciples into - I thought of wooden planks left to stand up without supports.

And then I experienced sucha confusion about how to do this, one thing after the other. I'm talk-ing days, weeks, spent working on it.

Moving away from them, he fell with his face to the ground, and he shouted, and I heard it like this: "O unnameable my Father!", whom when he was a boy he had known from his teaching was the creator, the maker of all - was I AM THAT I AM, no more personal or defined a name possible - only now he says "Father". Why not "Mother"? I don't know why not "Mother", I would have cried for mine, I do now.

I hope you have seen what I have asked you to imagine, before I scrubbed it all out. When I went wandering again, to that place where the remains of the crater are, boarded over, as it turned out, under turf, I felt so drained I wanted only to lie down under the yew, let it spike me. Melodramatic? Yes, yes, of course, and true.

He said - and I think he said this quietly, soberly - "If it is possible, I want to escape this, but if you, I AM THAT I AM, Father, have marked me out for this." And did he, Jesus, hear yes, and whisper yes, or sigh only? How to paint this, to begin again? You see here now a wide-open mouth. I thought: "And that's all;" it fills almost the whole canvas, then added an overflooding as well of dark cloud, the tiny specks of brightness, not stars but bluster, he is meeting I AM.

WE LIVE in time that is never the present - often tense, yes, sorry - which is only ever the past becoming the future. We are told and then, and then; it seems an incurable this, then that; so how to paint to make present everything that happened in that light-dark-light, if it's not to be a comic strip?

Look, I painted over and out the great open mouth, and over the darkening sky and the spots of light, do you see? All grey again. Then in bed, sleepless, I wished I hadn't.

Next morning, I knew I had been right to do it, the moment-by- moment was evolving into consequences. He returned to his disciples, and saw they were asleep. I saw him then as a force of nature. I would show him as storm, as storm in the form of a winged dark thing without boundaries, a hawk-angel bursting open the very air.

When he said, to Peter especially, "Couldn't you men stay awake to protect me, not even for an hour?", look, on the canvas now, a splash of his red voice, addressing shadows with splinter wounds for ears.

I was stopped again, held back. What if he had said it not in anger, but as gentle as gentle could be: "Couldn't you men, my friends, stay awake to protect me, not even for an hour?" So I made him a waif and stray who'd wandered away and got lost. He was crying, even.

The canvas becomes a confusion of tracks and loose doors, a nightmare of an arm here, some stray heads, eyes adrift, the sky as when the forecaster says, apologetically: "Watch out, today will be changeable."

And then I felt I was back in junior school, and I'd had my eye on someone's half-eaten pudding and custard, and they were looking away, and the teacher is behind me, and says: "Don't do it: you won't like yourself afterwards."

If not my talent, fill my stomach! Spare a thought for the disciples: "Not even for an hour?" They'd failed. They were confused, I was confused. They had wanted glory by association; I wanted, by enchantment or luck, to acquire more of the wherewithal and applause as a painter than I could ever - "Watch and pray so that you will not fall into temptation. The spirit is willing, but the flesh is weak."

Yes, yes, heard that a million times, but such lovely pudding and custard!

WORSE than stalled, I turned the painting to the wall, and for days walked, and walked - walked anywhere, wanted to give up this absurd dancing with shadows, get a proper job. Then, one stray bright afternoon, I had drifted back to the site of the bombed church, restless, mind elsewhere if anywhere, careless, wanted to feel careless; felt my feet touch wood under the grass, stamped on it a little, and it gave way.

I was on my back in the bomb crater - hard earth, dank smell, some sharp rock or remains of wall - seemed stuck, couldn't move, not badly hurt, I thought. Shocked, yes; alarmed, certainly. Tried to think whether I could haul myself out, started to panic.

An elderly woman came along, stopped, stood at the edge of what had opened up, looked down at me, knelt at the edge, and had hold of me. She was strong, with a will, had me almost hauled out, when she slipped. So there we were, half in, half out of this dank hole, holding on to each other.

We were lying awkwardly, me thanking her, she saying no, no, till a couple of young men in suits came by, looking puzzled, smiling then when we did - we smiled, we smiled! Of course we did - and get us out of here, please! - helped us out, all jollification.

The woman and I had a brief hug, brushed the earth off. I wanted to do something to thank her, she was shaking her head, smiling still, and went, looked back, waved, and as I stumbled home, I knew I would turn the large canvas and again confront it.

It has been handed on to us, scribe by scribe: "He went away a second time, and prayed." Why pass it on and tell it like that? The once would be good enough, anyway, for a painting. It nagged at me: the second time was more - desperate. What did he expect? Did he think that I AM THAT I AM Father would have had a change of mind? "Dad?"

No response whatsoever from I AM THAT I AM is recorded. No sound at all out of the Almighty Father. He wasn't listening? He heard and was indifferent? They - earthly - earthy - son and heavenly - hidden - father - being of one mind, was it that nothing needed to be said? How, facing the canvas again, to paint this? And whether to continue with that scrambled canvas, or to start a fresh one.

I HAD beome sick with the painting and overpainting, it was becoming ever more absurdly, as it seemed, game-playing. Take responsibility for it, man! Yes, but it had seemed given.

Now, in the story, a doublebind: "My Who-is-and-who-knows Father, if you can't release me from this horrible crisis, except that I accept it." How to paint that?

Look now, all the disciples are snuggled up together fast asleep, and look, in a corner up to the right, a dove fixed in a broken cage is hanging from the sky, I don't know why.

Now, the whole scene is grey-washed out again. Came the next day, and what I thought I wanted was a sepia photograph of Jesus running back to the disciples, a snapshot. He had, though, in every way gone further out, and now: "Are you still sleeping and resting? Listen, my time's up, this is it, the Son of Man is to be delivered into the hands of sinners. Get up! Let's go! Who is this coming? You know who it is, he has betrayed me."

And his sweat was like blood. And his sweat was like blood; what would you want to see on the canvas here now? I attempted a portrait, and I understood then the iconoclastic argument. Brushed it out.

But I am a painter. That image is now behind what you see here as a grey wash, and you can see also outstretched ragged hands. All this, while you have been looking at these hands. I shall take the canvas away, and paint over them.

Thank you for being here. No, no questions, please; honestly, I need a drink and some fresh air alone. Thank you for watching. Thank you.

The Revd David Hart is a former chaplain at Birmingham University, a theatre critic, and an arts administrator. He is now a writer of prose and poetry.