A certain heathen asked R. Yochanon ben Zakkai: The rites you perform in connection with the Red Heifer smell of witchcraft! You bring a heifer, burn it, grind it and take its ashes. You sprinkle two or three drops on one of you who is contaminated with corpse defilement and say to him, You are clean. Said R. Yochanan b. Zakkai to him: Have you never been possessed by a demon? He answered: No. Have you ever seen a man possessed by a demon? He answered: Yes. – And what do you do for him? – We bring herbs and make them smoke beneath him, and throw water on him and the demon is exorcised. He answered: Let your ears hear what your mouth has spoken. The spirit of defilement is the same as your demon. We sprinkle on it the waters of purification and it is exorcised.
After the heathen had left, R. Yochanon’s disciples said to him: Him you have put off with a straw, but what answer will you give us? He replied to them: By your life, neither does the dead defile nor the water purify, but the Holy One blessed be He said: it is a statute I have laid down, a decree that I have decreed and you are not authorized to violate my decree. (B.T. Pesachim 40A)
