A fraudster persuaded fellow churchgoers to hand over millions of pounds to fund his extravagant lifestyle, a court has heard.
Lindani Mangena, from Romford, Essex, posed as a City trader to persuade 1,000 Seventh Day Adventists from south London to invest in his bogus business.
Some lost homes and life savings as a result, Southwark Crown Court heard.
Mangena was found guilty of fraudulent trading, money laundering and carrying on an unauthorised investment business.
Fellow fraudsters Dean Hinkson, 29, from West Croydon, and Curtis Powell, 31, from Thornton Heath, were found guilty of inviting people to engage in the fraudulent investment.
Remanding them in custody for sentencing on Monday, Judge Peter Testar said immediate imprisonment was inevitable.
The court heard that Mangena, 24, opened a headquarters in the City of London to carry out the crime between July 2003 and March 2004.
Through his JNL Distributions business he, Hinkson and Powell offered a string of bogus investments, promising investors guaranteed profits of up to 3,000% in just six months.
Prosecuting, Stephen Winberg said Mangena took "ruthless advantage" of the trust and common religious beliefs he shared with his clients.
"The victims were much more ready to believe what they were told because it came from members of the same tight-knit religious community," he said.
As a result scores of pensioners and widows, as well as "cleaners and others in similarly humble jobs", parted with large sums of money.
The men took a minimum of £3.2m from investors, the court heard.
Mangena then spent "large chunks" of the money on luxury flats, Mercedes and other expensive cars and travelling to luxury hotels.
Mangena did not give evidence in the trial. Through his barrister he said he had set up a legitimate business in good faith, only for it to be corrupted by his greedy co-defendants.
But after more than 26 hours of deliberation the jury unanimously found him guilty.
The jury could not reach a verdict against a fourth defendant, Jordan Huie, 25, from Brixton, south London.
He was allowed bail pending a Crown decision whether to pursue the case against him.