Concerned that the boys were hurting the dog, he went over and asked, "What are you young fellows doing with that poor dog?"
One of the boys replied, "This dog is just an old neighborhood stray. We all want him, but only one of us can take him home. So we've decided that whichever one of us can tell the biggest lie will get to keep the dog."
Of course, the reverend was taken aback. "You boys shouldn't be having a contest telling lies!" he exclaimed. He then launched into a ten minute sermon against lying, beginning with "Don't you boys know it's a sin to lie," and ending with "Why, when I was your age, I never told a lie."
There was dead silence for about a minute, and then, just as the reverend was beginning to think he'd gotten through to them, the smallest boy gave a deep sigh and said, "Oh, all right, give him the dog."