Ezekiel 33:31-33

31They come to you as people come, and they sit before you as My people, and they hear your words, but they do not practice them; for with their mouth they express loving devotion, but their heart goes after their (unlawful) gain.

32Behold, you are to them like a love song by one who has a pleasant voice and plays well on a stringed instrument [merely to entertain them]; for they hear your words but do not practice them.

33So when it comes to pass—as it most certainly will—then they will know [without any doubt] that a prophet has been among them.”