Ezekiel 33:31-33

31And they come unto thee as a people cometh, and they sit before thee [as] my people, and they hear thy words, but they do them not; for with their mouth they shew much love, [but] their heart goeth after their dishonest gain. 32And behold, thou art unto them as a lovely song, a pleasant voice, and one that playeth well on an instrument; and they hear thy words, but they do them not. 33And when this cometh to pass (behold, it will come), then shall they know that a prophet hath been among them.