The Rev Rex Humbard, one of America's premier televangelists, died on Friday at the age of 88.

Humbard died of natural causes at a South Florida hospital near his home in Lantana, Florida, said family spokeswoman Kathy Scott.

The son of Pentecostal evangelists, Humbard hit the television airwaves in 1949 when the visual medium was largely untapped by evangelists. In 1952, weekly Sunday messages began broadcasting from his nondenominational Cathedral of Tomorrow, a renovated theatre that seated 5,400 people, in Cuyahoga Falls, Ohio.

His ministry flourished as did those of his contemporaries Billy Graham and Oral Roberts.

Coming out of radio broadcasting, Humbard was impressed with the power and magnitude of television when he viewed in 1952 one of the first television programmes broadcast live to northeastern Ohio. He was watching the Cleveland Indians-New York Yankees baseball game through a window in O'Neil's Department Store in Akron, Ohio. It was then that he set out to build a church and his own studio broadcasting facilities.

"The vast majority of people do not go to church, and the only way we can reach them is through TV," he wrote.

"We must go into their homes - into their hearts - to bring them the gospel of Jesus Christ."

According to his son, Charles Humbard, president of Gospel Music Channel, the televangelist was the first minister to broadcast a church service on television on a weekly basis.

By the 1970s, the "Cathedral of Tomorrow" broadcast appeared on more TV stations in America than any other programme, Humbard claimed. At the show's peak, weekly Sunday audiences averaged eight million viewers and up to 20 million worldwide.

One of Humbard's regular viewers was Elvis Presley and Humbard spoke at Presley's funeral in 1977.

In his 1971 autobiography, Miracles in My Life, Humbard shared, "I am proud to be an electronic evangelist for I believe that God has a plan - a plan to get into the homes and hearts of mankind for Jesus."

By 1979, Humbard drew global audiences with the show broadcasting in Canada, Europe, the Middle East, East Asia, Australia and Latin America.

In the December 1999 issues of US News & World Report, Humbard was listed as one of the Top 25 Principal Architects of the American Century.

"What America needs is an old-fashioned, Holy Ghost, God-sent, soul-savin', devil-hatin' revival!" Humbard would admonish audiences.

His messages were simple. He stressed "moral truths" and stayed out of politics.

"Seek the Saviour," Humbard would urge viewers, and all other moral problems will solve themselves.

Time magazine previously described Humbard's television services as a "blend of folksy, pep-talk piety and bubbly, inspirational hillbilly music".

His ministry expanded to include Mackinac College in Michigan, the Real Form Girdle Company in Brooklyn, an office tower in Akron and his own private jet.

Financial overreaching, however, rocked the ministry with television airtime alone costing nearly $2 million and millions of dollars in loans. Federal and state regulators complained that his church was selling unregistered securities to followers and not informing them that the cathedral lacked funds to insure repayment.

Humbard left in 1982 and moved to Florida. There he sought a base from which to expand its worldwide ministry into Latin America. Meanwhile, the congregation in Cuyahoga Falls dwindled and Cathedral of Tomorrow was sold to fellow televangelist the Rev Ernest Angley in 1994. Still, Humbard continued speaking to live audiences and his ministry continued to sell his tapes and books.

"Dad never retired," said his son Don in 2006, according to The New York Times. "He just changed direction. He wanted to make more special appearances."

Don is treasurer of the Rex Humbard Ministry Inc.

Besides Don and Charles, Humbard is survived by two other children, Rex Jr and Elizabeth, and his wife of 65 years, Maude Aimee.