Father Dave Smith preaches a message of peace from the pulpit - but one of his hobbies doesn't quite fit that image.

The 57-year-old Anglican priest has competed as a professional boxer for the past three years and believes neither his age nor profession is a barrier to his life in the boxing ring.

"I'd like to think I've become reasonably notorious over the years- both as a social activist and a priest, but also as a fighter," he told SBS News.

"I'm 57. But I'm fitter than I've ever been."

SBS News

What has proven a barrier to his life in the boxing ring, though, are regulatory authorities.

He most recent bout - scheduled for Sydney's Punchbowl on 22 March - was unexpectedly called off by the Combat Sports Authority, the governing authority for the sport in NSW.

The authority said it takes the safety of all boxers seriously, and it determined the 57-year-old's match against 32-year-old Jason MacGura was not safe.

That's disputed by Father Smith, who said he's passed the necessary medical tests, and had his registration approved.

Supporting Father Smith is Dr Lou Lewis, who has been a ringside doctor at many boxing bouts.

"I have cleared Father Dave in the past- and I wouldn't hesitate to clear Father Dave again, having known his past history, and knowing the man as he is today, and his level of fitness, and his ability," he said.

But the Australian Medical Association believes there’s no safe age to box.

“We should consider banning boxing totally,” NSW president Dr Kean-Seng Lim told SBS News.

“And so this is not a case of there's a safe age to do is. The official position of the association is no safe age.”

But there's more than just a sporting element to this pugilistic tale.

The fight between Father Smith and MacGura was set to raise money for the Boxers For Peace program, which allows the cleric to take groups of boxers to war-torn Syria.

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The program is said to be eye-opening for the boxers, and a source of hope for the local people in Syria.

Father Smith said the cancellation of the fight has been hurtful in more ways than one.

"It has discredited me before my own fans as a boxer. And, frankly, it's destroyed my ability to raise the funds I need. Boxing can be a great tool for social change," he said.