Nothing But Dust at Church

A woman attend a church service with her daughter. During the offertory prayer, the visiting minister waxed eloquent. He began, with arms extended toward heaven and a rapturous look on his upturned face,"Without you we are but dust... " He would have continued but at that very moment the woman's very obedient daughter (who was listening very keenly) leaned over to her mother and asked quite audibly in her shrill little girl voice, "Mom, what is butt dust?"