Yard sale

Little Johnny is having a yard sale. The local preacher stops by and notices a lawnmower for $15.00 and he buys it. A week later, the preacher shows up at little Johnny's house and tells him that the mower will not run. Little Johnny tells the preacher, that it will run but you have to curse at it to get it to start. The preacher says that he has not said a cross word in over thirty years. Little Johnny says......"Keep pulling on it.........they will come back to you"