For nearly 30 years, millions have visited the tiny village of Abadiania in remote, central Brazil to see a man some call the most powerful spiritual healer since Jesus and others call a charlatan.
"Primetime" followed the journeys of five people who sought out the man known as "João de Deus" -- "John of God" -- and took a closer look at the amazing claims that surround him.
The first traveler was Matthew Ireland, of Guilford, Vt. who was told he had a quick-growing inoperable brain tumor. He had undergone radiation and chemotherapy treatments. But almost two years after he was diagnosed, and after three visits with João, his tumor has shrunk.
Annabel Sclippa of Boulder, Colo., has not been able to walk since her spinal cord was nearly severed in a car crash in 1988. But after six visits with João, she says she can now feel sensation in her legs and can nearly balance herself standing between handrails -- something her physiotherapist said was unusual with her type of injury.
Mary Hendrickson of Seattle was diagnosed with chronic fatigue syndrome and powerfully debilitating allergies. She now feels much more energetic. "There is no way I would feel this way if something hadn't changed inside me," she told "Primetime Live." "Something's made a difference."
David Ames, of San Francisco, was diagnosed with Lou Gehrig's disease in April 2003. His nervous system was slowly disintegrating, and faced almost certain death -- only 10 percent of patients survive for 10 years or more. He has had no physical improvement, but he still says his spirit has gained from his visit.
And Lisa Melman of Johannesburg, South Africa, discovered a year ago that she had breast cancer. After visiting João, her doctor told her it had grown, although less aggressively than he expected it to and that she should still have surgery.
João is not a licensed doctor. Born in 1942, he is said to have been so rebellious he was thrown out of school after the second grade and could not keep a job.
Then, at 16, the story goes, the "entity" of King Solomon entered his body, and performed a miraculous healing. For years, João wandered Brazil offering healings. Twenty-seven years ago, he took residence in his casa in the plateaus and became known as "John of God."
Today, more than 30 doctors and notables can enter his body, João says. They're the ones that do the healing.
Among those luminaries are Dom Inacio de Loyola, a 15th century Spanish nobleman; Dr. Oswaldo Cruz, who helped to eradicate yellow fever; and the late Dr. Augusto de Almeida, a meticulous and demanding surgeon.
The "incorporating" happens in an instant, without warning. As João prepares to operate, his body suddenly jerks. He is said to take on the personality and even the eye color of the entity who inhabits him.
John of God's patients typically stay at Abadiania for two weeks, but they can stay for as long as they want. They can stay for an afternoon or morning and leave if they want to. Some people even arrive via bus on day trips.
Everyone is told not to stop taking their medications or treatments such as chemotherapy. After seeing John of God, there are some strict rules: for 40 days, no sex, alcohol, pork or pepper, which are all said to weaken the body's aura, or energy field.