The Torah in Parashat Kedoshim (19:31) forbids practicing the “Yidoni” form of witchcraft. The Sefer Ha’hinuch explains that this refers to the ancient practice to take a bone of a certain species of bird (called the “Yadua”), place it one’s mouth, offer incense and perform other rituals. This would result in a voice coming from the bone and providing information about the future. The Sefer Ha’hinuch references in this context his discussion regarding the previous prohibition, which forbids a similar form of witchcraft called “Ob.” There he explained that the Torah forbade such practices because they have the effect of compromising one’s Emuna. If a person feels that he can “outsmart the system” by receiving information about the future, then he will not place his trust in G-d. Moreover, these practices are closely associated with pagan worship, and for this reason, too, the Torah strictly forbade fortune-telling and witchcraft, in order to distance us from idolatry. As in the case of “Ob,” one who performs the “Yidoni” ritual in the presence of witnesses who had issued a warning is liable to Sekila. If he transgressed without witnesses or a warning, he is punished with Karet. If one consulted with a “Yidoni” practitioner and acted upon his advice, he is liable to Malkut. This prohibition applies in all times, in all places, and to both men and women.