The magical mystical tour: Why are the relics of St Thérèse such a holy hit?

Saint Thérèse, or what's left of her, is about to arrive in Britain for the first time – but is she a holy Roman circus act or an icon for our times? Joanna Moorhead reveals how a long-dead young nun from northern France became a 21st-century superstar

One afternoon in a few weeks' time a train will pull into the Eurotunnel terminal at Folkestone, and a hearse containing an unusually ornate coffin will drive carefully on to the platform to meet it. The hearse will then thread its way out on to the motorway before setting off through Kent to a church where a small band of people will be waiting eagerly to pay their respects.

There will be prayers, and maybe a hymn or two, but no tears. The occupant of the coffin, after all, died more than a century ago: she was a young girl from northern France who entered a Carmelite convent at the tender age of 15, before dying nine years later of tuberculosis. Her name was Thérèse Martin, but to her welcoming committee in Kent, and to the hundreds and maybe thousands of people across the UK who will gather round her coffin in the month that follows, she is St Thérèse of Lisieux; and the point of bringing her body to Britain, they would say, is not to mourn her life, but to celebrate it.

So begins the extraordinary – some think bizarre – phenomenon of a long-dead, sainted nun on tour. Because for four weeks from 16 September, Thérèse's hearse will criss-cross Britain, travelling from Portsmouth to Plymouth, from Manchester to Middlesbrough, from Leeds to Lancaster. At each venue – and there are 22 in all, including Wormwood Scrubs prison in west London – there will be services, and opportunities for both believers and the merely curious to pay their respects. It's the first time Thérèse will have been to the UK, but her coffin has certainly seen a bit of the world: her remains have so far toured more than 40 countries including the US, Australia, Iraq, Mexico and Siberia. Immediately before the UK she'll have been in Guyana, and after her British tour she leaves for Tunisia. She's quite probably the world's best-travelled corpse – which is particularly ironic given that she spent almost all her 24 years of life in one place, the town of Lisieux in northern France.

The globetrotting started in 1997, the centenary of Thérèse's death. Part of her body (her remains are split between caskets, so that some always remain in Lisieux) had been taken on a regional tour across France and then the bishops in Brazil requested a visit. Since then it's snowballed beyond anyone's expectations. Sister Monique-Marie, the nun who organises the tours, says she's continually amazed by the requests. "It certainly wasn't planned for the relics to do so much touring: it was just that one request led to another, and now we're booked up until the end of 2010. Wherever she goes, Thérèse pulls in the crowds – and it's not just people who go to church, it's all sorts of people. We can't explain what's going on," she says.

But despite the fact that it's become so widespread, even many Catholic churchgoers perceive Thérèse's posthumous wanderings, 112 years after her death, as mystifying. Some are outwardly hostile, calling it "a circus" and shaking their heads in horror at the ghoulishness. Cardinal Basil Hume, head of the Catholic Church in England and Wales until his death in 1999, seems to have had his doubts: despite the fact that he was said to have been particularly devoted to the saint, he blocked attempts for her remains to come here while he was in office. It wasn't until his successor, Cardinal Cormac Murphy-O'Connor, was approached two years ago that the champions of her cause got the green light to go ahead with the trip.

But who was Thérèse Martin – and why, instead of being laid to rest, is she enjoying a peripatetic eternity? The answers to these questions lie in Lisieux, an unremarkable town in Normandy that lost most of its centre during heavy Second World War bombing raids (although, miraculously some might say, the buildings associated with Thérèse were unscathed). It's an hour-and-a-half by train from Paris, and the first thing you notice, as you step out of the station, is the vast, white basilica that dominates the skyline, built in the 1930s and 1940s after Thérèse was canonised, as a place of worship for the pilgrims who began to flock here.

Thérèse's legacy is everywhere in Lisieux: the shops groan with memorabilia, rosaries, bookmarks – and the ubiquitous plaster statues which depict a figure in traditional Carmelite garb (black veil, white wimple, brown scapular, cream cloak), clutching a crucifix and several stems of red roses to her breast. This is the image of Thérèse I know from my Catholic childhood: the Thérèse whose statue adorns a million Catholic churches across the globe, the girl-nun who died tragically after a short lifetime of self-sacrifice, the so-called Little Flower ' (hence those roses) whose last promise was that she would shower down graces from heaven like a rose-petal rainshower.

That same Thérèse, unsurprisingly, is here in the Carmelite chapel in Lisieux. Her effigy, made of marble and wood, lies Sleeping Beauty-like in a glass casket, her face turned serenely towards the viewer, her cloak falling delicately around her shoulders and a tiny, almost imperceptible smile on her face. Strewn around the casket are flowers – roses, mostly – deposited by the hundreds of visitors who flock here each day to offer some prayers to one of the best-loved saints of the 20th century.

By any reckoning, Thérèse's rise to fame has been remarkable. When she died, in the infirmary of this convent, on 30 September 1897, her life seemed so pathetically uneventful that her sisters in the community wondered what the prioress could write in the traditional obituary that was dispatched to neighbouring convents. Then someone remembered that, a few years earlier, Thérèse had written a short autobiography, and it was decided to use that as the basis of a tribute. The tribute proved popular: its fame spread from convent to convent, and a second print run of 2,000 was ordered. When the nuns were left with some copies, they resourcefully decided to sell them, and Thérèse's autobiography, The Story of a Soul, has never been out of print since. It's been translated into 50 languages, and millions of copies have been sold worldwide.

What drew the millions of readers to her story was the tone of Thérèse's relationship with God. At a time when the Catholic Church championed a deity to be feared, distanced and obeyed, she unravelled a portrait of an intimate, almost brotherly love. For Thérèse, it wasn't so much that she needed God, as that God needed her. "We must not let slip," she wrote, "the smallest opportunity of giving Him joy... He is in such need of love." It was (indeed, in some ways still is) a revolutionary approach to a deity; so, too, was her insistence that it was in the small things of life – the everyday frustrations, disappointments and challenges – as well as in the big heroic deeds, that a love of God could be demonstrated. Her "little way", she called it.

Thérèse's approach to God was to appeal – particularly, in the years soon after her death – to the soldiers of the First World War battlefields not far from Lisieux. For thousands of soldiers who found themselves facing an early death amid the humdrum boredom of daily life in the trenches, Thérèse's mixture of the mundane and the immortal spoke volumes: she became known as "the Angel of the Trenches", and the museum at Lisieux contains hundreds of tokens of gratitude – including medals awarded for valour – brought here by soldiers, mostly French but some British or even German, who felt her words had guided them through the darkest of times. Many made a pilgrimage here, to pray at the grave where her remains still were at the time; as well as the soldiers there were other devotees including, it is said, the family of Edith Piaf who brought their little girl, then aged seven and unable to see, to Thérèse's grave – according to some reports, her sight was miraculously restored following the visit.

Eventually this story and others like it, emanating from a far-flung corner of France, reached Rome. Bishops were instructed to investigate, and Thérèse, a young, consumptive, virginal nun who had devoted her life to a loving God, seemed a perfect candidate for canonisation. In May 1925 she was declared a saint by Pope Pius XI, an elevation that ensured yet more pilgrims would be pouring into Lisieux, and for many decades to come, to worship her memory and to throw their roses at her marble effigy.

But there was more to Thérèse Martin than is conveyed in her plaster sainthood: the Church's gloss of innocence and perfection has, across the decades since, obscured a very human young woman who was no stranger to suffering, and in whose heart – even towards the end of her life – there lurked grave doubts. To find the real Thérèse you have to leave the basilica and the Carmelite convent in Lisieux and climb the hill to a handsome, rather well-to-do house called Les Buissonnets, which was the Martin family home. Here, in dark, oak-panelled rooms, Thérèse was raised – but, tragically, it was a motherless childhood. Zelie, whose ninth and final child Thérèse had been, died of cancer when she was only four years old.

Even before Zelie's death, the family had known plenty of sadness: four siblings died in childhood, leaving Thérèse with four older sisters one of whom, 16-year-old Pauline, took on the role of substitute mother ("darling mother", Thérèse calls her in The Story of a Soul). Their father, Louis, the local watchmaker, did his best for his five daughters, but it was Pauline to whom Thérèse was closest – it's hard to imagine how difficult the wrench must have been when, six years after their mother's death, Pauline decided to become a Carmelite nun. Adding insult to injury, three years later another sister, Marie, also entered the Carmel. Can it really have been such a surprise that Thérèse, despite being still a teenager, felt that her life, too, lay within the convent walls?

Because she was so young, Thérèse had to battle with the Church authorities for permission to become a Carmelite, even going to the lengths of travelling to Rome with her father to petition the Pope himself. Eventually, in 1888, she joined her sisters in the convent only to discover, as she settled into Carmelite life, that it wasn't quite the nirvana she had hoped it would be. There were difficult relationships, especially with the prioress and with the novice mistress; she also found the behaviour of some of her fellow nuns extremely irksome (one of them, apparently, chattered her teeth the entire time in chapel, driving the new recruit almost to distraction).

Added to all this, outside the convent her father – due, some said, to losing a third daughter to the Carmelites – had suffered a serious breakdown, and was being nursed by the two sisters who remained at home, Céline and Léonie. Inside the convent, Thérèse was beset by doubts: was there really a God, and a heaven? In her autobiography, she writes about her "dark night" and of how she is mocked by a voice which tells her to "Hope on! Hope on! Look forward to death! It will give you, not what you hope for, but a night darker still, the night of utter nothingness!" The difficult times, she wrote, were like "a wall which reaches to the very heavens, shutting out the starry sky". And the doubts plagued Thérèse right to the end: just weeks before she died, she told one of her fellow nuns that "I don't believe in eternal life... it seems to me that after this mortal life there's nothing more."

It's this mixture of suffering and doubt, tragedy and difficulty, that make Thérèse a saint for our times, according to Father Michael McGoldrick, head of the Carmelite order in England and one of those who'll be travelling the country with Thérèse's remains next month. "I think she appeals to people because of her sheer normality. She was the product of a dysfunctional family, she had a tough time growing up, she found much of her life hard-going, and she had huge doubts. A lot of people relate to all that. She isn't a saccharine saint, although I do think she's been portrayed as one over the years. But now she's being reassessed, and when the sugar coating is off people find they rather like Thérèse."

The question is, will touring her remains further his ambition to make more people aware of who she was – or will putting a coffin on show simply turn people off? McGoldrick is adamant it's not just about a coffin: what's important here, he says, is that the relics are a link with Thérèse, and taking them on tour gives people the opportunity to engage with her story and to reflect on the life she had. "There's a lot of power around a body. Wakes are very powerful occasions. There's something about gathering around a coffin that makes you talk about the person it once was – and that's what we're hoping is going to happen with Thérèse in the next few weeks." He's optimistic – wildly optimistic, some might say, given the ungodliness of our age – that the British will be out in force for the planned events. "I was in Ireland when the relics visited there and the response was remarkable. They say 2,000,000 people turned out to see her coffin... Maybe it won't be so big here, but I think we could be surprised by how popular the services are. The humanity of the woman shines through, and people are very drawn to that."

Back at the Carmel in Lisieux there are still nuns who remember Thérèse's sisters – as well as Pauline and Marie a third sister, Céline, eventually entered the convent. (The fourth sister, Léonie, obviously the rebel of the family, became a Visitation nun instead.) Sister Marie Lucille, who has been a Carmelite for 60 years and is now in her eighties, remembers Céline, who died in 1959. "We knew her as Sister Genevieve," she says. "She was a very lively person, and she was a very keen photographer – she was given permission to bring her camera into the convent with her, which was very unusual in those days." Indeed Céline's photographs of Thérèse, both before and after she became a nun, are another key to her fame – it's extremely unusual for Carmelite nuns to be photographed as Thérèse was, especially doing the ordinary things of life. Céline's camera captured Thérèse haymaking, doing the washing, sitting chatting in the convent garden – even acting in a convent play in the role of St Joan of Arc, the saint she eventually was to join as co-patron saint of France.

The day I meet Sister Marie Lucille has seen the profession of a new nun that morning. The life the sisters lead in the convent, she says, is not so different from how it was in Thérèse's time – although, unlike many Carmels, the one here is flourishing. It's another legacy, she is certain, of the Little Flower. "So," she says as we part, "Thérèse is coming next to England. People will like her there, I think. She led a simple life, but it was a life full of love – and though she has been dead a long time, she still has things to teach us about life."

Go to www.catholicchurch.org.uk/index.php/ccb/catholic_ church/relics_of_st_therese_of_lisieux for details

Relics around the world

The word relic comes from the Latin reliquaiae, meaning remains. According to Church teaching, relics are classified according to how closely associated they were to a holy person: Thérèse's relics, since they are body parts, are "first-class" relics. An item that a saint wore or used, such as a glove or veil, is a second-class relic, while an item he or she merely touched is a third-class relic.

Santiago de Compostela is a city built on a relic – the remains of St James, which were acknowledged by the Pope as genuine around 800AD. Since then, millions of pilgrims have walked across Europe to pray there.

Relics are venerated in other faiths, too. The Temple of the Tooth in Kandy, Sri Lanka (right), houses the upper canine tooth of Buddha, which according to legend was taken as he lay on his funeral pyre. Meanwhile hair from the beard of the Prophet Muhammad, and a collection of his teeth, are kept in the Topkapi Palace in Istanbul.

The basilica at St-Maximin-la-Sainte-Baume in Provence is home to a casket containing a skull which is said to be that of Mary Magdalene, who according to legend spent her last days in a cave in the region.

More recent saints are revered through relics, too. The church of St Cajetan in Hamrun in Malta has a phial of blood taken from St George Preca as he lay dying in 1962.

In 2008 a seller posted a picture on eBay of an envelope said to contain remains of St Bartholomew, but the website prohibits the sale of human parts and they were withdrawn. The Church, too, forbids the commercial use of relics. JM