He survived an ambush in Afghanistan, helped tend the wounded in aftermath of the Bataclan attack and now he has saved a priceless relic.
Four years earlier Father Fournier helped to nurse the wounded when 89 people were massacred at the Eagles of Death Metal concert at the Bataclan in 2015.
Etienne Loraillere, an editor for the French KTO Catholic television network, said Father Fournier 'went with the firefighters into Notre Dame Cathedral to save the Crown of Thorns and the Blessed Sacrament', Mailonline reports.
This was confirmed by an emergency services source who said: 'Father Fournier is an absolute hero.
'He showed no fear at all as he made straight for the relics inside the Cathedral, and made sure they were saved. He deals with life and death every day, and shows no fear.'
Hundreds of firefighters tackled the blaze through the night, battling to stop it wreaking complete destruction of the treasured facade after flames torched the roof, sending its spire crashing to the ground before crowds of horrified Parisians.
The blaze broke out at around 5.50pm BST on Monday and took until 9am to bring under control.
The 19th century spire collapsed and was destroyed along with much of the roof.
And while hundreds of million euro have been pledged to fund the repair project it is feared there are no trees big enough to replace the timbers in France.
Visiting the scene on Monday night, French president Emmanuel Macron said a national subscription would be launched to rebuild the national monument.
It was reported that billionaire French fashion mogul Francois-Henri Pinault had pledged 100 million euros (£86 million) towards the effort.
“Notre Dame is our history, our imagination, where we’ve lived all our great moments, and is the epicentre of our lives,” Mr Macron said.
The first harrowing images from within the fire-ravaged cathedral began to emerge as firefighters brought the blaze under control.
A smouldering pile of what appeared to be the charred remains of the roof and spire lay smoking in front of the altar, while a cross that had escaped destruction glowed from within the gloom.
Read more from Yahoo News UK:
Gilded candlesticks, artworks and furnishings were among the treasures seen being rushed from the cathedral by a “human chain” before being bundled into trucks by police officers.
Some of the cathedral’s most precious objects, including a relic purported to be the crown of thorns worn by Jesus Christ on the cross, were whisked away to a secure facility.
Peter Riddington, a consultant director with Donald Insall Associates, which oversaw the restoration of Windsor Castle following the 1992 fire, said he felt a solution would have to be found.
He added: “The history of the cathedral is so strong that to rebuild it in a form that isn’t what people understand Notre-Dame to be, what it symbolises and what they believe it to be would be a very difficult argument to win.
“There will be a lot of soul searching I think.”
While Windsor Castle was a straightforward rebuild due to the “cellular” structure of the rooms Mr Riddington said Notre Dame’s status as a place of worship - and a large one at that - presents extra challenges.
Windsor saw some 1,500 workers help rebuild and restore the castle at a cost of around £36m, 27 years ago - though both the cost and the four year project came in ahead of schedule and under budget.
He said: “I think it’s a much bigger, more difficult rebuild.
“One thing I would say though is that it is not the first cathedral fire over the years.
“The west wing at York was badly damaged in the 1980s but they do get restored.”