The Devil doesn’t like Latin.

That is one of the first things I learnt from Father Gabriele Amorth, long known as Rome’s chief exorcist, even though that has never exactly been his formal title. Perhaps Rome’s chattiest exorcist is the more apt title. Now past the age of 80, Amorth has dedicated the last decades of his life to regaining for exorcism a measure of respectability.

Despite his advancing age, he continues to perform the rite several times a week at his office in Rome. Scores of people seek him out. He prefers to use Latin when he conducts exorcisms, he says, because it is most effective in challenging the Devil.

A little over a decade ago, Amorth founded the International Association of Exorcists, which holds a secret exorcists’ convention in Italy every two years. He is the group’s president emeritus. On alternate years, the national association of exorcists meets, also with Amorth in attendance.

Father Amorth has had a hand in recruiting, training, or inspiring many of today’s exorcists. In Italy the number of exorcists has, remarkably, grown tenfold in the last decade, by Amorth’s count. As he slows his pace ever so slightly – old age and the rigours of a strenuous vocation catching up to him – he has overseen a new generation of exorcists and helped to fuel a global renaissance of the ritual. Devil detox these days is something of a growth industry: in a world awash in catastrophe and unspeakable suffering, many people feel increasingly compelled to see evil in concrete and personified – not to mention simplified – forms, and to find a way to banish the bad.

But how is evil defined and conceptualised? Is evil, as many people believe, merely the absence of good – privatio boni – a metaphysical concept? Or is evil a force, a physical entity, that acts? Is evil personal or impersonal? Is the Devil a symbol or something concrete and real? It is this latter view of evil that is held by many priests and other Catholics for whom exorcism is an acceptable practice, because if evil is an active force, there must be a remedy, a way to combat it.

Many critics, however, see the Church’s willingness to use exorcisms at all as a perilous crutch. It allows people to take flight from personal responsibility and constitutes not just a wilful ignorance of serious mental illness but also, potentially, an exacerbation of such illness.

Where psychiatry and therapy require a person to look within to solve his or her problems, exorcism and blaming the Devil allows a person to escape introspection and instead discern only external causes for problems. But Amorth and other practitioners quickly dismiss the criticism. “Exorcism is God’s true miracle,” Amorth likes to say.

“We of the Bible know that evil spirits are angels created as good by God and who then rebelled against God,” Amorth said during one of our chats at the Society of St Paul congregational residence in suburban Rome, where, in a back room, he conducts exorcisms. “But the idea of evil spirits is a universal idea, in all cultures, all religions, all times. Naturally, everybody defends themselves according to their own culture and mentality . . . perhaps resorting to witchdoctors or what have you. But all people, all the time, have a perception that spirits of evil exist, which it is necessary to protect against.”

Recognising demonic possession – the “discernment,” as it is called – is the first and very difficult aspect of an exorcism. This is most commonly achieved by seeing how the patient responds to religious symbols such as holy water or a crucifix. For example, the person has a great aversion to entering a church or cannot bear to face a priest.

It must be said: Amorth and other exorcists insist that true demonic possession is extremely rare. In fact, of the thousands of Italians who seek exorcisms for themselves or for relatives, the priests say, few really need them. In most cases, the exorcist does not perform a full-fledged exorcism, but rather offers a prayer of “liberation,” which includes some of the same incantations but does not involve the full ordeal.

Officially, the Roman Catholic Church today is adamant about one thing: the need to establish that a person seeking an exorcism is not mentally or physically ill. This requirement is emphasised in the revised exorcism rite, which was formulated in 1999. Many exorcists say they work with psychiatrists and physicians to determine the nature of the patient’s affliction. However, in practice, exorcists disagree on the need for doctors to participate. Amorth usually asks the person seeking the exorcism whether he or she has first consulted a doctor (almost always they say they have) and he will take them at their word.

Like a number of the older exorcists, Amorth sees a diagnostic role for the exorcism itself. He maintains that the exorcism is the only procedure that can truly and definitively determine whether a person is afflicted by satanic influence. Only an exorcism, in his opinion, can overcome the tricks the Devil uses to conceal his presence. The consequence of this is that some exorcisms take place without the consent of medical personnel. Since an exorcism is basically prayer, Amorth reasons, it can’t hurt. “An unnecessary exorcism never harmed anyone,” he says, rather controversially.

It is exactly that attitude that worries doctors, in Italy and elsewhere, who approach the subject of demonic possession and exorcism much more sceptically, or who think it is completely bogus. Ignoring physiological causes and medical advice risks exacerbating the patient’s condition, they say. Furthermore, an exorcism can be highly suggestive, and a susceptible patient could be convinced that he or she is possessed and could begin to display the symptoms out of imitation, compliance, or a subconscious need to please the priest.

“You promise something to someone who is very sick and at best you offer a temporary cure,” says the philosopher Dr Sergio Moravia of the University of Florence. “It’s a scam.”

Amorth counters with the argument that people who come to him for exorcisms or healing prayers do so only after having recurring symptoms despite treatment from a host of doctors. If they had not exhausted medical possibilities, they would not knock on his door.

By some estimates offered by Italian mental health organisations, thousands of Italians seek exorcisms every year. Amorth is reluctant to pinpoint a number, and he contends that, regrettably, many more people frequent practitioners of witchcraft and black magic. Whatever the number, there is no doubt that demand has soared.

As Amorth put it in one of his essays: “Why, today, is there such a high demand for exorcists? Can we make the case that the demon is more active today than in the past? Can we say that the incidence of demonic possession and other, lesser, evil disturbances is on the rise? The answer to these and similar questions is a decisive. Yes. Rationalism, atheism – which is preached to the masses – and the corruption that is a byproduct of Western consumerism have all contributed to a frightening decline in faith.

“This I can state with mathematical certainty: where faith declines, superstition grows.”

Guidelines from The Roman Ritual

- Possession is not to be taken lightly. Each case is to be carefully examined and great caution is to be used in distinguishing genuine possession from certain forms of disease.

- The priest who undertakes the office should be himself a holy man, of a blameless life, intelligent, courageous, humble, and he should prepare for the work by special acts of devotion and mortification, particularly by prayer and fasting (Matthew 17:20).

- He should avoid in the course of the rite anything resembling superstition and he should leave the medical aspects of the case to qualified physicians. He should admonish the possessed, insofar as the latter is capable, to dispose himself for the exorcism by prayer, fasting, confession and communion.

- The exorcism should take place in the church or some other sacred place, if convenient; but if on account of sickness or for other legitimate reasons, it takes place in a private house, witnesses (preferably members of the family) should be present: this is specially enjoined, as a measure of precaution, in case the subject is a woman.

- All idle and curious questioning of the demon should be avoided, and the prayers and aspirations should be read with great faith, humility and fervour, and with a consciousness of power and authority.

- The Blessed Sacrament, or the host, is not to be brought near the body of the obsessed during exorcism for fear of possible irreverence; but the crucifix, holy water, and, where available, relics of the saints are to be employed. If expulsion of the evil spirit is not obtained at once, the rite should be repeated, if need be, several times.

- The exorcist should be vested in cassock, surplice, and a violet stole.

© Tracy Wilkinson 2007. Extracted from The Vatican’s Exorcists, to be published by Little Brown on July 5 at £16.99 and available from Times Booksfirst for £14.99 (free p&p), 01326 555745, timesonline.co.uk/booksfirst