UPDATE: Bill Cosby has responded to this news with a statement to ET.
In a fury of Twitter updates, comedian Norm Macdonald reveals a number of behind-the-scenes details about the Saturday Night Live 40th Anniversary show, including who was originally supposed to impersonate Bill Cosby on "Celebrity Jeopardy."
VIDEO: SNL 40th Anniversary Special's 9 Greatest Segments of the Night!
While the '90s SNL alum and former "Weekend Update" anchor fired off more than 100 tweets in just over two hours, the messages that have everyone talking revolve around Murphy -- who had his own tribute during the special -- declining to portray Cosby.
"He knew the laughs would bring the house down. Eddie Murphy knows what will work on SNL better than anyone," Macdonald tweeted. "Eddie decides the laughs are not worth it. He will not kick a man when he is down."
Current SNL cast member Kenan Thompson ended up doing the impersonation instead.
The 51-year-old comedian continued: "Eddie Murphy, I realize, is not like the rest of us. Eddie does not need the laughs. ...Eddie Murphy is the coolest, a rock star even in a room with actual rock stars."
NEWS: Bill Cosby's Accusers: A Timeline of Alleged Sexual Assault Claims (Updated)
Given all the current controversy surrounding Cosby, do you think Murphy made the right decision not impersonating him?