In the past few years the Harrison St Community Church has gradually increased its numbers, from 10 to 25.
The secret, according to pastor Phil Husband, is the church's relationship to its local community.
It has launched a programme called "Our Street", which is aimed at the immediate area around the church, located on the corner of Harrison St and Liverpool St.
"We're only a little church and we can't save the city. But what we can do is help out in our street.
" "Our Street" takes in Harrison St, Keith St, Niblett St and the surrounding area - about 200 or 300 houses in total," Mr Husband said.
He said the idea of "Our Street" was not a hand-out but a hand-up - and it was a two-way relationship.
For the last two years, the church has held several community breakfasts, and has other plans in the pipeline. Hundreds of people have turned up for the community breakfasts, with the result that a few more locals have been making their way to the church. Some of them eventually join the church, while others become part of the church community, doing maintenance work around the church or just stopping in for a chat.
"We're getting away from the church being a building, and taking it out to the community."
The church's pastoral worker, Brent Siddall, spends a lot of time in the community, visiting anyone who is sick or in need of company, and organising community events.
Mr Husband said the initiative was not aimed at attracting more numbers to the church.
"If we get more people, that's great, but that's not why we're doing it. We're doing it because that is what Christians do."
Mr Whitfield said the Lutheran Church was "quite traditional", but could learn a lot from the approach of the Harrison St Community Church.
He said it was the first time in about 30 years the Lutheran Church convention had been held in Wanganui.
"Our convention is held every two years, and we always try to make it somewhere different each time."
Mr Whitfield said it was a way for the church to take stock and plan for the next few years.