How can We Know?--There are bad spirits as well as good, and the vital question is: How can we know the difference between them? Let us at this stage consult an expert--for there are such--one who came in contact with spiritual forces to a marvelous extent, not only receiving messages from other worlds, but also interviewing the messengers. Joseph Smith knew the difference between good and evil communicants, and here is his testimony concerning them: Expert Testimony.--"When a messenger comes, saying he has a message from God, offer him your hand, and request him to shake hands with you. "If he be an angel, he will do so, and you will feel his hand." [An angel is a resurrected being, with a body as tangible as man's.] "If he be the spirit of a just man made perfect, he will come in his glory; for that is the only way he can appear. "Ask him to shake hands with you, but he will not move, because it is contrary to the order of heaven for a just man to deceive; but he will still deliver his message. "If it be the Devil as an angel of light, when you ask him to shake hands, he will offer you his hand, and you will not feel anything [he also being without a body]. You may therefore detect him." [8] In another place, the Prophet says: "Wicked spirits have their bounds, limits and laws, by which they are governed; and it is very evident that they possess a power that none but those who have the Priesthood can control." [9] To his declaration that "a man is saved no faster than he gets knowledge," he adds that if men do not get knowledge, including the knowledge of how to control evil spirits, the latter will have more power than the former, and thus be able to dominate them. This is precisely the condition of "the spirits in prison." They are dominated by a power which they cannot control. They are in Hell, and Satan sways the scepter over his own dominion.