Bill Cosby thanks Eddie Murphy for refusing to play him on 'SNL40'

Comedian and movie star Eddie Murphy returned to the "Saturday Night Live" stage Sunday to celebrate the show's 40th anniversary special.

Murphy was on-screen for a few minutes, as himself, after being introduced as a cornerstone of the show, who, when its ratings were on the ropes, very well may have saved it.

Instead of doing any jokes, Murphy just spoke about his enduring feelings for the show and what it meant to him.

Well, as it turns out, there is more to the story, according to former "SNL" cast member and 40th anniversary special writer Norm Macdonald.

For more than an hour Wednesday night, Macdonald, who was one of the writers of the enormously popular "Celebrity Jeopardy" skit, tweeted about the special.

Another writer got the idea to include Murphy in the skit, which would bring "the house down," Macdonald said.

But Murphy said no -- and for a specific reason.