I thought that maybe he was sporting a beard to teach the lesson of that episode, but then I went on to the next episode, and the next, and the next. It appeared that the beard would stay! I don't know if this lasts the whole rest of the series, but I sure hope not.
Though all his various TV shows, The Cosby Show, I-Spy, Kids Say The Darndest Things, Cosby, never have I ever seen Bill Cosby with a beard. I think it scares me.