The 38th prohibition is that we are forbidden from inquiring information from the dead — as is imagined by those who are truly dead,1 even though they eat and feel — that when one performs certain actions and dresses a certain way, the deceased will come to him in his sleep and answer the questions he was asked.
The source of this commandment is G‑d's statement (exalted be He),2 "Among you there shall not be found anyone...who attempts to communicate with the dead."
Our Sages said in tractate Sanhedrin,3 "The verse,4 'who attempts to communicate with the dead,' refers to someone who starves himself and sleeps in the cemetery in order that an impure spirit shall rest upon him."
One who transgresses this prohibition is punished by lashes.
