By Stephen Walsh, CNN

(CNN)– They preach, they heal the sick, and they swagger from the pulpit. But these aren't your average preachers, they are children dubbed pint-sized preachers. The viral internet phenomenon is transitioning to TV in a new documentary.

On Wednesday at 10 p.m. ET, the National Geographic Channel will air “Pint-Sized Preachers,” a documentary looking inside the controversial world of child evangelists and the families who watch over them.

The hourlong documentary tells the stories of three young boys who have gained notoriety for their explosive sermons and, in one case, a self-proclaimed power to heal the sick with a single touch.

Will the documentary have the same cringe-inducing effect on viewers as, say, TLC’s “Toddlers and Tiaras”?

That may depend on what they believe.

Consider 4-year-old Kanon Tipton.

Videos of the boy firing up his congregation have been a hit on YouTube . But one has to wonder, is he copying his evangelist father, or is he actually compelled to preach by the power of the Holy Spirit?

“With Terry Durham and Matheus Moraes (the two other boys featured in “Pint-Sized Preachers”), they’re repeating what they’re reading,” executive producer Stuart Clarke said. “With Kanon, it’s slightly different.”

Tipton’s parents have said in interviews that it’s a bit of both: They admit Kanon does mimic his father, but they do believe he’s touched by the hand of God.

Clarke and director Tom Dumican, both British, said they were compelled to work on the documentary because child preachers and American-style fervor over religion do not exist in the United Kingdom.

“I think our audiences will be quite jaw-dropped by this phenomenon,” Clarke said.

National Geographic Channel will show the documentary in Britain at a later date, the network said.