The Bible (Deut. 18:9-11) forbade Israelites to engage in "the abominations of the nations" whose land they were to inherit, specifically singling out "any one that makes his son or his daughter to pass through the fire, or that uses divination, or is an observer of times, or an enchanter, or a witch, or a charmer, or a consulter with familiar spirits, or a wizard, or a necromancer." Various prophets also denounced superstition. Thus Jeremiah stated, "Do not hearken to your prophets, nor to your diviners, nor to your dreamers, nor to your enchanters, nor to your sorcerers" (Jer. 27:9). Nevertheless, various superstitions have prevailed at different times. The Talmud, for example, discusses
Astrology, with R. Joshua ben Levi implying that persons born on a specific day of the week all share certain character traits, though R. Johanan rejects the idea that there are various times which are more propitious than others. The idea of auspicious or inauspicious times is found in the
Shulḥan Arukh (
OH 551:1), which states that "from the beginning of the month of Av, a Jew who is involved in a legal case with a non-Jew should attempt to postpone it, because the time is not auspicious."
The Talmud (Sanh. 65 a-b), when discussing the verses in Deuteronomy 18, explains some of the superstitions which are involved. Thus "an observer of times" (me'onen), according to R. Akiva, is one who reveals propitious times for leaving on a journey, or for purchasing objects, or for harvesting one's crops. "An enchanter" (menaḥesh) is one who sees omens in various everyday events, such as dropping bread or a staff, or having a deer cross one's path, all of these being considered bad omens.
The Talmud mentions various other superstitious practices, to some of which it gives credence, while others it finds senseless. In certain instances, the practices are condemned as being against Jewish law. R. Akiva, enumerating those who have no share in the World to Come, mentions a person "who whispers [verses of the Bible as charms] over a wound" in order to heal it (Sanh. 10:1). Maimonides nevertheless writes in the Mishneh Torah ("Laws of Idolatry" 11:11) that "if a person was bitten by a scorpion or by a snake, one is permitted to whisper on the wound ... in order to calm him and strengthen his heart, even though it is utterly valueless, for given the fact that his life is in danger, [the sages] permitted it, so that he should not go out of his mind."
The Talmud speaks of certain actions which to the modern mind would seem to be needless superstition, such as forbidding a woman to walk between two men. Great attention is also paid to the implications of Dreams, with an entire literature developing on how to "rectify" bad dreams.
Other areas of superstition revolve around the Evil Eye. The Talmud and especially the Kabbalah have many references to evil spirits and Demons, and their effects. Maimonides dismisses all of these, stating that demons do not disturb anyone who ignores them. In order to ward off evil events, the Talmud discusses the comparative efficacy of various Amulets.
Throughout the Middle Ages superstitions either persisted or were added, to the extent that R. Judah He-ḥasid, in his Sefer Ḥasidim (Sect. 59), mentioned various practices that were unavailing and even in violation of Torah law. These superstitions included not eating eggs on the night after the Sabbath and not taking fire twice from the same source if there was a sick person or a woman who had given birth in the house. Yet Sefer Ḥasidim also enumerates many practices and omens which it claims are valid; for example, if a new house is built on the same site where another had stood earlier, care must be taken to ensure that the doors and windows in the new house be in exactly the same place as the old one, for otherwise "one's life is in danger from the demons or the angels."
Certain customs which are practiced to this day have also come under attack as being superstitions, although many classic sages have believed in them. These include the Tashlikh ceremony on Rosh Ha-Shanah, where all one's sins are figuratively thrown into the water, and Kapparot before the Day of Atonement, in which sins are figuratively transferred to the hen or rooster which is used in the ceremony.