Imam Sadiq (peace be upon him): A person asked Imam Sadiq (peace be upon him) about various matters ... He said: "What is the origin of sihr (magic)? How does the sorcerer gain power over those strange feats that people speak of? And what does he do?" The Imam (peace be upon him) said: "Sihr is of several different kinds: one kind is like the science of medicine. Just as physicians have a remedy for every ailment, sorcerers likewise have an affliction and trial for every state of health and calm, and a sickness and trouble for every well-being and soundness, and have devised a trick for every matter. Another kind is sharp-wittedness, quickness of action, sleight of hand and dexterity. And one kind is the use of the shaytans (satans) with whom they have a connection." He said: "How did the shaytans come to know sihr?" He said: "By the same route through which physicians came to know medicine; some of the knowledge was found by experience, and some is treatment and remedy." He asked: "What do you say about the two angels named Harut and Marut, of whom people say that the two teach sihr to individuals?" He said: "They are a means for testing and trial. Their tasbih (glorification) is like this: 'Whoever does such-and-such today, such-and-such will happen to him; if he treats himself with such-and-such a thing, such-and-such will occur.' Whatever they say, kinds of sihr are learned; but the two angels say: 'We are only a trial for you. Do not take from us that which harms you and does not benefit you.'" He said: "Can the sorcerer, by means of his sihr, turn a human being into the form of a dog, a donkey, or something else?" He said: "He is more incapable than that, and weaker than to make any change in the creation of Allah. Whoever alters the composition of a form that Allah has established is a partner with Him in creation, and Allah is far exalted above having any partner. If the sorcerer had such power, he should be able to remove diseases, distresses, whitening of the hair, poverty and hardship from himself. The greatest act of the sorcerer is namimah (tale-bearing), which causes separation between two friends who love one another, and brings about bloodshed, the ruin of homes, and disgrace. The tale-bearer is the worst of persons who has ever set foot upon the earth. The most correct saying about sorcerers is that which is on a par with medicine. The sorcerer treats a person, and [through austerity and never marrying to the end of his life] he abstains from intimacy with women. But the physician treats the same patient by a method opposite to the sorcerer's, and he is cured."