@Green Witch,
												Just to be a bit more specific.  To me, it seems a basic comedy act or bit where a character, not necessarily a mohel,  picks on someone, for a small thing, like putting a glass on a table, and exagurates, or embellishes to a incredible degree, all the bad things that could happen, when the glass falls on the rug.  This can be duplicated for endless situations.  I suspect it to be an old comedy act.  I suspect it is not original to Seinfeld at all. just a clever reconstruction of tried and true comedy sketch, probably from Vaudeville,  or the Catskills or somewhere.  However, I can't prove it.