To that end, several years ago he founded the Sunday Afternoon Cycling Club, he holds workshops on making trailers in his backyard and he refurbishes and gives away bicycles to low-income people.

Needless to say, he also does most things you can think of with a bike trailer, plus a few you probably can’t.

Mr Muir says he founded the Sunday Afternoon Cycling Church in Christchurch as a means of worshipping God other than meeting in darkened church halls, singing songs and listening to speakers.

“I really connect a lot more with God out in the sunshine, on my bike on the Port Hills or something like that. That’s where the idea for the cycling church came from, to encourage a sense of worshipful activities but outside a church setting.”

He started a regular cycling group with some friends, and out of that came a book,  Profound Revelations of a Sunday Afternoon Cycling Church (Prosacc).

This was partly a reaction against a Christian community which sometimes takes itself too seriously and partly to stimulate some serious reflection about what more meaningful forms of church might look like in an age where many people struggle to find spiritual meaning in the institutional church.

Not many are involved as far as the cycling activities go, but Mr Muir puts more energy now into encouraging people to take up cycling, building trailers and promoting care for the environment.

He saw the light regarding the environment after reading Green Christianity, by Tim Cooper. “When you stack all the scriptures up, I found them quite compelling. This is a serious biblical mandate. To care for the environment is as spiritual an activity as being a missionary or living in the slums of Manila, or being a doctor or pastor of a church.

“We are called to do this as Christians, and I think it needs to get bumped up the priority list a bit.  “Christians have quite a prophetic role to play. Everyone has become much more aware of global warming, and the impact on the environment in a myriad of ways. So it would be good if Christians could lead the culture.

“In the 1970s, greenies and hippies were into the environment, so Christians backed off it. To be involved in the environment was to be associated with new age heresy, which was ‘the enemy’. That was an unhelpful attitude.

“But things have changed. The Christian community is now more aware of our task to care for God’s creation, and accept that as part of the gospel. It just needs to translate into some serious action.

“By and large, Christians in New Zealand go along with our consumer culture and live very affluent lifestyles. We need to be aware of the tension between that and Jesus’ teaching on not accumulating things.”

When you visit the Muir household’s small property, you are almost overwhelmed by bicycles and bits. They are stacked in every conceivable place, and a front bedroom has been converted to a workshop.

In a shed in the tiny front yard between the house and street are road bikes, mountain bikes, a people-mover bike and tandem attachments. Wife Carolyn has three, plus the children’s bikes.

“We’re not a naturally athletic family, and it does take some encouragement to get them on the bikes,” he says. “But once we get out and about we have a great time.” Daughter Petra learned to ride a bike just before she turned 3.

To encourage others, he buys old bikes at garage sales, does them up, then gives them away. So far he has given away about 35. Not much gets wasted. He made a tandem from an old exercise machine bought for $2 from the City Mission, plus the bike trailer.

Mr Muir’s first trailer was made from an old iron-frame bed, and he has published the plans at his internet site, www.cyclingchurch.org.nz He says that using this method, you can build a trailer for no more than $20.

“But it is long-winded, and if you want to take over the world with bike trailers – as I do – you need something more efficient.”

He now uses aluminium tubing, which is lighter and quicker, and offers kitsets for about $100. Some of the skills are no doubt similar to those he uses in his job in the bio-engineering department at Christchurch Hospital.

The trailer was the answer to the challenge of how to get heavy loads around. “For instance, I played bass guitar at church, and I’d have to take the car, which frustrated me. My first heavy load was my bass amplifier and guitar, which worked very well.”

The family use the trailers for the obvious, such as doing the weekly shopping, but there is also a trailer to tow the family canoe to the beach, and he even built one to carry a fridge. This was done as part of a supermarket challenge he has organised the last couple of years.

This year’s challenge pitted three bikes against three cars, each travelling to different supermarkets at varying distances from Cathedral Square. Bikes and cars each had to carry two children and pick up a week’s worth of groceries.

“A couple of years ago I would have said there is no way you can do that on a bike. But I found it’s a remarkably good way of doing the shopping.”

It poured with rain on the day of this year’s challenge. Despite that, not only did the bikes beat the cars in two cases (the other was a draw, largely because of a five-minute toilet stop for one of the children), in one case the car took twice as long as the bike for the return journey.

And despite the rain, the cyclists rated the journey much more positively than did the car drivers, who were frustrated from being stuck in long queues of traffic.

Like all true prophets, Steven Muir finds himself disappointed at the lack of response to his message.

“There’s definitely room for improvement. I guess I have a big vision – I would like to see supermarket carparks full of bike trailers and the odd car for someone who can’t get on their bike.

“The roads are still frustratingly congested with cars. A lot of people could bike, but the easy thing is just to jump in your car, because it’s a habit that’s been developed.”

With congestion on Christchurch roads becoming almost as bad as Auckland, it’s a message that might soon be heeded more readily, though.

John McNeil, a veteran of 40 years of newspaper and radio journalism, is South Island editor for Challenge Weekly, New Zealand’s non-denominational, independent national Christian newspaper.