He says the Virgin Mary speaks to him on the 13th of each month at 3pm, that he is destined to be the last Pope and can "cure" the deaf and blind.
From his compound at Cambewarra, outside Nowra, William Kamm - known to followers as The Little Pebble - has spent the past 20 years chronicling his visions for the future and running a worldwide religious sect linking itself to the Catholic Church.
After a four-year investigation involving the Vatican, the church yesterday officially outlawed Mr Kamm's Order of St Charbel.
The decree orders the cult to disband and Mr Kamm to stop linking his order to the church, which finds most of its practices and Mr Kamm's supernatural prophecies "offensive."
Mr Kamm, who claims the Virgin Mary gave him the name Little Pebble to protect his real identity, has grown his order to 500,000 members in 160 countries.
The self-styled prophet, who is not an ordained priest, claims to have been the vehicle for more than 500 prophecies from Mary and even Jesus Christ after God spoke to him in a grassy paddock in 1984.
He said yesterday his strike rate as a "seer" of the future was about half, with about 250 prophecies coming true - but he won't reveal which ones.
He wrongly predicted a massive natural disaster which would force the cancellation of the 2000 Sydney Olympics and an earthquake which would flood most of Sydney after the partial destruction of Warragamba Dam. He has predicted the end of the world "as we know it" at Easter 2004.
Wollongong bishop Peter Ingham said yesterday the sect had sparked family breakdowns on the south coast and had been the target of the church for nearly two decades. The sect's teachings were "false, harmful and contrary to the Catholic Church", Bishop Ingham said.
"If Mr Kamm considers himself a loyal Catholic, he would not want to operate outside the church or encourage others to do so."
Three successive bishops have tried to shut the sect since 1984.
After issuing the decree, the church has now taken the rare step of setting up a phone service to counsel members of the cult, which include more than 300 people at the 100ha Cambewarra property as well as communities in Victoria, Queensland and South Australia.
Mr Kamm rejected the decree yesterday and said his order would flourish. He instead called for a "proper" canonical investigation into his visions in a bid to prove his prophet status.
"I operate on the authority God gave me ... and I will continue my work," he told The Daily Telegraph at the Cambewarra compound. "God spoke to me and told me to form an order in the church and that is what I have done. I'm not leaving the church because it's persecuting me.
"We haven't been excommunicated. We will continue."
Mr Kamm - who believes he will become Pope Peter I, the last pope - has threatened to sue the church worldwide for allegedly defaming the order in its attempts to discredit his visions.
The sect was also linked in 2000 with the doomsday Ugandan cult the Movement for the Restoration of the Ten Commandments of God, whose 735 members died in one of the worst mass suicides in history.
The Little One who hears the word of God The Little Pebble claims to have received 5156 prophecies. Predictions that have not been fulfilled include: