A man went to a pet shop and purchased a parrot. It belonged to a Jehovah's Witness because it kept repeating, "Read the Watchtower and Awake", "Avoid worldly association", "The end of the system is near". SQUAWK!
The new owner attempted to add new vocabulary to its repertoire with books and tapes and contemporary music, but as the months went by it became obvious that nothing could break through. The parrot continued to repeat the standard catchphrases of the Watchtower Society and nothing else.
The owner finally became frutstrated and infuriated and in a fit of violent anger threw the parrot across the room. The parrot smashed against the wall and slid to the floor, at which point it immediately started squawking, "No Blood!" "No Blood!"