Going Public Excerpted and adapted from a shiur by Dayan Yehoshua Grunwald January 28, 2021…
Excerpted and adapted from a shiur by Rav Moshe Zev Granek
January 14, 2021
And the necromancers did likewise with their whisperings to bring out the lice, but they were unable . . .
The Rambam (Hil. Avodah Zarah 11) lists the types of witchcraft and sorcery that are forbidden by the Torah. He writes that all of these are lies and falsehoods; they have no real power and are only tricks and illusions used to fool people.
This statement seems to contradict many Gemaras, as well as numerous pesukim, that speak of witchcraft as a real but impure power. The Rishonim and Acharonim suggest several answers to this problem, each of which is problematic.
I would like to offer another possible answer. In Hilchos Yesodei HaTorah, the Rambam says that a navi (prophet) must prove himself with a sign, like successfully predicting the future, in order to be accepted. But how, the Rambam proceeds to ask, is this a sign of prophecy—perhaps the man is a sorcerer who can see the future through the forces of impurity? He answers that sorcerers are only correct some of the time and are always wrong about some of their predictions, so if a person is consistently correct, he must be a true navi. It emerges from this Rambam that practitioners of witchcraft might indeed see the future, but they do so unreliably. Perhaps he refers to witchcraft in Hilchos Avodah Zarah as falsehood because it is always partially wrong, unlike the powers of holiness which are always completely accurate.
A source for the Rambam may be found in our pasuk: The sorcerers were able to perform some of the same wonders as Moshe—turning staffs into snakes, turning blood into water, and making frogs appear—but they could not conjure lice. This may be because the powers of impurity only work sometimes and are unreliable.