Isaac Hayes who voiced the character of Chef quit South Park in 2006.
Isaac Hayes' son has revealed the real reason his dad quit South Park.
The legendary singer, who died in 2008, voiced the Chef character in 136 episodes between 1997 to 2006.
But he quit the show in 2006 not long after an episode called Trapped in the Closet aired that poked fun at his religion, Scientology.
At first Hayes didn't seem that bothered by the episode, telling A.V. Club at the time: "They (Trey Parker and Matt Stone) didn't let me know until it was done.
"I said, 'Guys, you have it all wrong. We're not like that. I know that's your thing, but get your information correct, because somebody might believe that sh*t, you know?'
"But I understand what they're doing. I told them to take a couple of Scientology courses, and understand what we do. [Laughs.]"
Just a few months later though, Hayes' attitude about the episode had changed completely and he issued a statement announcing he had decided to quit the show.
"There is a place in this world for satire but there is a time when satire ends and intolerance and bigotry toward religious beliefs begins," the statement said.
"Religious beliefs are sacred to people and at all times should be respected and honoured. As a civil-rights activist of the past 40 years, I cannot support a show that disrespects those beliefs and practices."
After Hayes quit, one of the South Park creators told MTV that they would release the soul singer from his contract.
"This has nothing to do with intolerance and bigotry and everything to do with the fact that Isaac Hayes is a Scientologist and that we recently featured Scientology in an episode of South Park," Stone said.
"In 10 years and over 150 episodes of South Park, Isaac never had a problem with the show making fun of Christians, Muslims, Mormons and Jews. He got a sudden case of religious sensitivity when it was his religion featured on the show."
But now, 10 years later, Hayes' son has revealed to The Hollywood Reporter that his dad did not quit the show because of the Scientology episode.
"Isaac Hayes did not quit South Park; someone quit South Park for him," Isaac Hayes III said.
"What happened was that in January 2006 my dad had a stroke and lost the ability to speak. He really didn't have that much comprehension, and he had to relearn to play the piano and a lot of different things. He was in no position to resign under his own knowledge.
"At the time, everybody around my father was involved in Scientology - his assistants, the core group of people. So someone quit South Park on Isaac Hayes' behalf. We don't know who.
"My father was not that big of a hypocrite to be part of a show that would constantly poke fun at African-American people, Jewish people, gay people - and only quit when it comes to Scientology. He wouldn't be that hypocritical."
South Park co-creator Parker told The Hollywood Reporter that deep down they knew Hayes was forced to quit the show by senior figures in The Church of Scientology.