The Rabbis say that on the Sabbath serpents and scorpions may be tamed
by charming; that a metal ring, such as may be carried on the Sabbath,
may be applied as a remedy to a sore eye; but that demons may not be
consulted on that day about lost property. Rabbi Yossi has said, "This
ought not to be done even on week-days." Rav Hunna says, "The Halachah
does not enjoin as Rabbi Yossi says, and even he prohibits it only
because of the risk there is in consulting demons. For instance, Rav
Yitzchak bar Yoseph was once desperately delivered from the attacks of a
vicious demon by a cedar-tree opening of its own accord and enclosing
him in its trunk."
THE TALMUD, _Sanhedrin_, fol. 101, col. 1.