Among the thousands who claim to have been cured by the healer known as "John of God" is Luiz Inacio Lula da Silva, the popular Brazilian ex-president, now said to be in remission from larynx cancer.
"I am going to cure you," de Faria told one young woman during a session in this small town in the central state of Goias. After going into a trance, he stuck a four-centimetre needle into the sole of her feet.
"Don't look, it's going to hurt," he warned her as he thrust the needle in several times.
The young woman apparently felt nothing and when it was over, the nearly illiterate faith healer flashed a big smile.
His patient, visibly moved, extolled that she had just been cured from a chronic illness which doctors could not treat.
Born on June 24, 1942, de Faria is an adept of spiritism, a religious doctrine based on the belief in the survival of a spirit after death.
Founded in the 19th century by Frenchman Allan Kardec, spiritism today is particularly popular in Brazil, where it has nearly three million followers.
The healer's entourage said de Faria paid several visits to the former president when he was being treated at a Sao Paulo hospital for a larynx cancer.
Lula however has refused to confirm or deny press reports that he met at least three times in Sao Paulo with the healer.
American TV show hostess Oprah has also visited the town to film the crowds who gather around the healer.
"John of God" says he communicates with spirits when he goes into a trance. He diagnoses diseases, prescribes medication and conducts surgeries, either with his hands, or with kitchen knives, scalpels or scissors.
"Since the age of eight, God has given me this energy. I don't heal. God heals," the spiritual healer told AFP during a brief respite.
He receives about 1,000 people a day, three times a week and more than half of them are foreigners.
The ritual is always the same: the faith healer sits in a big armchair, his feet on a cushion. In front of him and in adjacent rooms, several hundred followers and so-called mediums meditate to form an energy circle.
One by one, the patients then parade before de Faria who treats them, gives them instructions or calls them to come back for a surgery or treatment, often in less than a minute.
Miracle man or charlatan?
In one operation, performed without anesthetics, the medium opened up the eye of one patient and began scratching it with a knife, according to Reinaldo Daher, an orthopedic doctor who witnessed the operation.
"You could hear the scraping. The patient did not flinch and he told him: 'You are healed, you can go,'" Daher told AFP.
He fervently believes in the healer's powers. "I have to believe because I have seen it," he said.
But some, particularly in the medical establishment, are wondering whether de Faria is a miracle man or a charlatan.
"We have a major dilemma in Brazil. The constitution guarantees freedom of faith, which makes it difficult to take any actions against illegally practicing medicine or charlatanism," Emmanuel Fortes, audit director of the Brazilian Federal Council of Medicine, told AFP.
He stressed the council warns people against inconsistencies in some practices, as well as those which do not offer any guarantees.
"We do not recommend that patients abandon their traditional medicines and prescribed drugs."
Many of de Faria's patients turn to him as a last resort after being disappointed by mainstream medicine.
Others come seeking jobs or spirituality. And many just come to say thank you.
"All will be received," said a volunteer through a microphone. Instructions and spiritual messages are transmitted in English, French, Spanish, German, Russian and Portuguese.
"I arrived in 2006 with multiple sclerosis diagnosed in 1999. I had been in a wheelchair. And now you can see, I am cured and I can walk. My symptoms are gone," said Marina, a New York-based Russian woman who now comes several times a year to work as a medium and a guide in Abadiania.
For the past 35 years, John has been receiving patients and admirers in this small town where the economy revolves around his healing center.
There are more than 40 inns and dozens of taxis operating shuttle services to and from Brasilia airport.
There is no charge for the treatment. His centre maintains that its income comes from donations, sales of natural remedies and purified water.
But the skepticism from the Brazilian establishment remains.
"Operations in a contaminated environment and unnecessary therapies at religious events are illegal," the vice-president of the Federal Council of Medicine of Brazil, Vital Carlo, told Globo television.