The 34th prohibition is that we are forbidden from performing any act of witchcraft.
The source of this commandment is G‑d's statement (exalted be He),1 "Among you there shall not be found anyone...who practices witchcraft."
One who transgresses this prohibition intentionally is punished by stoning, as said in G‑d's statement (exalted be He),2 "Do not allow a sorceress to live." If he did so unintentionally he must bring a sin-offering,
The details of this mitzvah have been explained in the seventh chapter of Sanhedrin.3