In the middle of Arrowtown, up a gentle rise away from the shops and meandering tourists, sits a small, yellow stucco building, not quite dwarfed by the adjacent St Patrick's Catholic Church.

To pass beyond its bright green door is to enter a humble space book-ended by a colourful statue of Jesus and a life-size mannequin of Mary MacKillop. Yet perhaps more significant to this story is a small metal bell; slightly corroded and seemingly well worn, it sits on a window ledge along with a small note explaining its purpose: "Ring -hourly during recreation to remind sisters to offer prayer and work to God."

The bell is just one indication of the measure of MacKillop's service, both spiritually and pragmatically through the Sisters of St Joseph of the Sacred Heart, the order she co-founded in the South Australian outback in 1866.

Described as "an ordinary woman who lived an extraordinary life", her deeds will be recognised in the Vatican tomorrow, when she will be canonised and henceforth known as St Mary of The Cross.

Across the ditch, where she was born, a media storm is brewing: Australia's major daily newspapers are printing special editions celebrating the canonisation and no fewer than seven television stations are covering the event. Elsewhere, Catholic websites feature blogs detailing journeys from various points of the globe to Rome.

Sister Jill McLoughlin, of the Christchurch order of the Sisters of St Joseph, is among those heading to the heart of the hubbub, a pilgrimage she describes as "an awesome privilege".

"To witness her being canonised a saint will be a very special moment that I will treasure for the rest of my life.

"I am truly inspired by Mary MacKillop and the way she lived her life for the sake of others - especially how she reached out to those with few choices in life," says McLoughlin, who left on Tuesday with a contingent that included Dunedin Catholic Bishop Colin Campbell.

The pilgrimage group returns on October 24 in order to celebrate Mary's canonisation at each of the six Catholic Dioceses in New Zealand; special masses are being celebrated throughout November. "I certainly feel very proud to be a member of the Sisters of St Joseph and I celebrate Mary's sainthood with all my sisters and all those who resonate with the Charism of Mary MacKillop," McLoughlin says.

"The fact that Mary spent time in our country makes it all the more special for us in New Zealand."

Born in Melbourne in 1842, the eldest of eight children, Mary was committed to helping rural communities. Starting in the small South Australian town of Penola, her Josephite order's attempts to provide education and help for the needy spread through Australia, on to New Zealand and around the world.

Mary first visited New Zealand in 1883, establishing a school at Temuka.

She returned in October 1897, arriving in Bluff with three fellow Sisters. The parish priest of Arrowtown convinced the nuns to start a school in the village. Her work in the region is recognised in the name of Balclutha's Blessed Mary MacKillop Church, which will change its title to St Mary MacKillop this weekend. Name changes aside, there are other implications in Mary being made a saint. The canonisation will shine a light on an important role model, McLoughlin says.

"Mary was an ordinary woman who lived an extraordinary life. We need role models who inspire us to be compassionate, loving people. Mary's life of heroic goodness demonstrates for all of us a way to live with a generous and forgiving heart.

"My favourite saying of hers is, 'be calm and full of hope'."

Margaret Hyland, chairwoman of the committee organising activities in Arrowtown on the weekend of November 6-7 to commemorate the canonisation, believes MacKillop was 100 years ahead of her time.

"She was a young Australian woman. She was 25 when she started this order [and] within four years she had established 34 schools in South Australia.

"She was officially under the oversee of the bishops and it was in the Victorian years, when women did what they were told," Hyland says.

A member of the parish group that restored the Mary MacKillop Cottage in the 1990s, Hyland believes MacKillop's upbringing was far from privileged.

McKillop's father, Alexander, failed in several businesses and often left the family for extended periods. With her mother, Flora, in poor health, the eldest of eight children brought up the rest of the family. By the age of 14, having got a job in a Melbourne stationers, MacKillop was the main breadwinner.

"She was a battler and was also a very intelligent woman," Hyland explains.

"Despite her father's drawbacks, he was a very learned man and he made sure they all had a good education.

"She stood out. Education was her main thrust, but if she saw a need anywhere she would do something about it. If she saw an old man on the street, drunk, she would take him home and look after him. If she saw a prostitute dragging a kid around, she would take the child and put it in her school. She tried to get a refuge for beaten women.

"That was back in the 1860s - it was unheard of. This is where she got into trouble with the bishops. She was mixing with these people."

Hyland is referring to the fact MacKillop was excommunicated in 1871 for alleged insubordination before being reinstated four months later.

In 2009, a century after MacKillop's death, Archbishop Philip Wilson of Adelaide publicly apologised to the Sisters of St Joseph for the wrongful excommunication.

The story of MacKillop's excommunication has resurfaced recently, with initial news reports claiming she was punished for reporting child sex abuse by a local priest in 1870.

However, Father Paul Gardiner, of Penola, author of Mary MacKillop: an Extraordinary Australian and regarded as an authority on her history, claims he was misquoted and that MacKillop had no part in the sex abuse disclosure.

Though the scandal did occur in 1870 and was reported by the Sisters of Saint Joseph, MacKillop was in Queensland at the time, Gardiner told South Australian newspaper The Border Watch.

MacKillop took a significant step towards sainthood in 1995, when she was beatified by Pope John Paul II on October 17, recognition from the Vatican of a miracle - the healing of an Australian woman of terminal leukaemia in 1961.

To be named a saint, a second miracle (she is credited with curing a woman suffering inoperable lung and brain cancer in 1993) had to be assessed scientifically and theologically and then decreed by the Vatican.

"As far as the Church is concerned, there has to be some proof that she has achieved heaven and that she can intervene," Hyland explains.

"Mary doesn't cure people, only God can do that. But people will pray to Mary for intervention. It's a personal choice to believe in miracles. When a person goes to be canonised, the argument is put forward. There is also what is called a devil's advocate, who must dig through all the history and bring up every argument they can against the canonisation. It is very rigorously tested."

Not rigorously enough, according to Vicki Hyde, media spokeswoman for NZ Skeptics Inc, who says an unquestioning faith in miracles can do very real harm. "There are plenty of people who have prayed hard and died anyway, but their experiences do not make for heartwarming stories in the tabloids.

"If, by promoting the idea of miracles or even simply letting them go unchallenged, more people are encouraged to reject actual medicine and hope for a miracle instead, then deaths will result," Hyde says. "It is common for a broad variety of health outcomes to be attributed to miracles or divine intervention of some form, even when actual medicine has been used. We tend to see what are known as 'the usual suspects' in this regard - cancer remissions, cessation of chronic pain - typically associated with the back, rheumatism or arthritis - lifting of depression. What would be a miracle would be for an amputated leg to grow back."

Mary MacKillop: at a glance
* Born in Melbourne on January 15, 1842, the eldest of eight children to Scottish parents.

* Founded the Sisters of St Joseph of the Sacred Heart in Penola, South Australia, in 1866 with Julian Tenison Woods, a priest and scientist. An order committed to helping the needy in rural areas, it spread from Australia to New Zealand and around the world.

* First visited New Zealand in 1883, establishing a school at Temuka; returned in October 1897

* Arrived in Bluff in October 1897 with three of her fellow Sisters. Originally bound for Port Chalmers to open a school, Fr Keenan, the parish priest of Arrowtown, convinced them to start a school in the village first.

* Continued to Port Chalmers; returned to Arrowtown for St Joseph's Day on March 19, 1898; stayed for two months to supervise the completion of the school. Is believed to have passed through the South Otago area three or four times.

* Died in Sydney on August 8, 1909, aged 67.

* Beatified (the first step towards sainthood) by the late Pope John Paul II on October 17, 1995.

* Will be canonised in the Vatican tomorrow and henceforth will be known as St Mary of The Cross.

- Otago Daily Times