Baptism is terribly serious and theological.

On a purely practical level, it's also fraught with possibilities for disaster, especially if you're a Baptist. We practise full immersion, in which the candidate is submerged – temporarily – beneath the water. We know most other Churches baptise infants, but as we always say, you do it your way and we'll do it God's way.

However, I've sometimes thought that it must just be, well, easier to go along with the majority.

Baptist students at theological college are advised to practise beforehand in a local swimming pool. It must look odd, but at least it helps you get the mechanics right. Nothing, however, can prepare you for the actual event.

1. My former room-mate in college conducted his first baptism and made the mistake of standing too close to one end of the pool. Plunging the candidate backwards in the approved fashion, he banged her head on the edge. We all winced with him (and her) when he told the story; it could so easily have been any of us.

2. My own introduction to the art was a little less traumatic, but also eventful. My church was an old one in Baptist terms, having just celebrated its bicentenary when I went there. The baptistry – a very basic concrete model – hadn't been used for a while and when we arrived in the morning we found that most of the water had leaked out overnight. There was time to fill it up again before the service started, but not to heat it. There were 11 candidates (about half the youth group) and I was in the water for long enough to be chilled to the bone. My teeth chattered over the benediction.

3. Next time we were prepared, with the leak fixed and the baptistry painted a lovely shade of blue. It hadn't occurred to us that this would make the floor as slippery as a skating rink. Baptising a particularly generously-built man (I weighed about nine stone at the time) I lost my footing and we both went under, me with a badly wrenched leg. For the third attempt we repainted the floor and sprinkled sand on while it was still wet. Problem solved.

4. I recall another baptism, again of someone much heavier than me, where I was so worried about being able to get him back out of the water that I didn't quite get him under. Every part of him was immersed except his face. So was it an actual baptism or not? In that split second I had to decide whether to double-dip him, at some risk of his inhaling a lungful of water, or trusting in the grace of God for the last half-inch. I chose the latter, and he survived.

5. In the church I attend now, we had our first baptism for a few years not long after we'd redecorated. We arrived in the morning to find that the warmth of the water had turned the building into a sort of tropical house and that a large piece of plaster had fallen from the ceiling. That was two years ago, and needless to say it's still missing.

6. Clothing: that's another thing. What should the well-dressed candidate wear? White is traditional, and one of my churches had a complete set of women's gowns in various sizes, complete with lead weights sewn into the hem to keep them from floating upward. The trouble was that they'd been made from old sheets and were disturbingly revealing when they were wet. After one outing they were discreetly recycled and people just wore jeans.

We never had an actual tragedy, thankfully. People have drowned during baptismal services in the open air. Others have been electrocuted because of faulty heating or amplication equipment.

Baptism is a bit weird. It can be very funny. It's awkward and inconvenient, and sometimes it's dangerous. It also be a tremendous experience, with an unforgettable spiritual kick for candidate and congregation – and for the minister.

In my Baptist tradition, baptism is the moment when the free choice of a Christian believer meets the grace of God who calls us to follow Christ in a lifetime of discipleship. Because it's human, we'll mess it up sometimes. But that doesn't matter, because – like everything we try to do for him – God takes what we bring to him so imperfectly and incompletely and transforms it into a perfect offering.

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