Mishneh Torah — Negative Mitzvot מצוות לא תעשה, Chapter 31
The full Hebrew text of Mishneh Torah, Negative Mitzvot, Chapter 31, with English translation by Maimonides (Rambam).
שלא לקסום, שנאמר "לא יימצא בך . . . קוסם קסמים" (דברים יח,י).
Not to practice black magic, as [Deuteronomy 18:10] states: "There shall not be found among you... a magician."