The show already depicted Mohammed in Super Best Friends (2001). At that time, Comedy Central had no problems with airing it.
After the episode, The Simpsons sent South Park flowers and King of the Hill said they were "doing God's work."
As a matter of fact (or irony), Comedy Central refused to air an image of Mohammed, which would have been shown in the Family Guy (1999) episode within the show.
This episode starts with a clip from the "Terrance and Phillip Show." This was made to mislead the audience to believe that this episode would be about Terrance and Phillip instead about the four South Park boys on their way to get a certain Family Guy (1999) episode aired. This is a reference to Terrance and Phillip in Not Without My Anus (1998), which was the episode that aired after Cartman's Mom Is a Dirty Slut (1998) which had an immense cliffhanger. The "Not Without My Anus" episode had nothing to do with #1.13 and aired to fool the audience (it aired on April's Fool day). Many viewers were angry that they had to wait for another episode (Cartman's Mom is Still a Dirty Slut (1998)) until the story established in #1.13 continued.
Among the ideas on the balls are: date, Mexico, Gary Coleman, fishing, airplane, colon, laundry, eraser, Germans, Nicaragua, Stan, winning, truth, Britney Spears, anorexia, genius and pizza. According to the joke involving Mohammed other ideas must be: Mohammed, football helmet, fish and toga.