They preach the "Prosperity Doctrine" - that God can make you healthy and wealthy - and they live what they preach.

Every year America's best known TV evangelists bring in hundreds of millions of dollars from donors all over the world. But as BBC's Jonathan Beale reports, some of the evangelists' own lifestyles have begun to ring alarm bells and have prompted a Senate investigation into their activities.

Last fall, Senator Charles Grassley (R-IA), the ranking Republican on the Senate Finance Committee, began probing the finances of six TV evangelists whose lifestyles include mansions, Rolls-Royces, and private jets, all paid for out of church funds. Grassley told BBC, "I would not contribute to an organization that is Christian and evangelical with money being wasted that way."

Four of the ministers have since complied with the probe, but Rev. Kenneth Copeland, whose congregation recently bought him a $20 million private jet to preach the gospel, is holding out against the inquiry, which he claims is "aimed at publicly questioning the religious beliefs of the targeted churches."

"It's not yours, it's God's, and you're not going to get it," Copeland says of his financial records.  He has launched a website to publicize his crusade and has received support from several leading conservatives, including Paul Weyrich and Kenneth Blackwell.

This video is from BBC, broadcast July 2, 2008.

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