Amulets take many forms throughout the different periods of Jewish history. The use of amulets to ward off evil spirits and/or disease was pervasive in the cultures that surrounded ancient Israel, and numerous examples of Canaanite, Phoenician, Assyrian, and Egyptian origin have been recovered. The use of amulets by Biblical Israelites is specifically criticized in Is. 3:18-20. It is unclear from the context whether amulets qua amulets are being condemned, or whether they are merely included in a list of vanities and luxuries associated with women. Only two physical examples of amulets from the Biblical era have been uncovered so far. The first is a tomb inscription found at Khibet el Qom dating to the 8th Century BCE asking for the protection of YHWH and his asherah. The second is also a tomb artifact, but this one consisting of two rolled up copper plates inscribed with the Priestly Blessing (Num. 6:24-25) found at Ketef Hinnom and dating from the 7th Century.
Evidence for the use of amulets grows dramatically post-Biblically. II Maccabees 12:40 reports disapprovingly of slain Jewish warriors found wearing amulets with foreign gods inscribed on them. Again, it is unclear whether the author objects to talismans in general or to just these synchronistic examples. Of course, the tefillin worn by Jews on the head and arm to fulfill the commandment (Deut. 6:8) are regarded as having talismanic properties by some Jews, thought that is not their authoritative function. The standard Greek translation for tefillin, "phylactery," highlights this perception. Likewise, in some circles the mezuzah is regarded as a charm against misfortune.
The Sages are largely at ease with the use of amulets, discussing their use to protect people (particularly children), animals, and property. The Babylonian Talmud distinguishes between written amulets and folk amulets, the latter called kamia shel ikrin, made from roots (rather like a medicine bag). We have a number of written metallic amulets, mostly in Aramaic. Features of these charms include: Biblical phrases, power names of God, and strings of nomina barbara, or nonsense words and phrases. "Atbash" (letter substitution) codes are sometimes used. Often foreign loan words appear and, on occasion, unpronounceable divine and angelic names. Diagrams, magical alphabets, and crude illustrations are common but not constant features. Many written amulets were rolled up and inserted in metal tubes, paralleling the way a mezuzah is protected and displayed.
Amulets were considered a regular part of the medical response to illness and the Sages speak of experienced kamia makers who have a proven track record of making efficacious amulets. They also discuss the criteria for judging a good medical amulet (Shabbat 61b; Yoma 84a). They do, however, place limits on the sanctity with which amulets may be treated, even ones with God's name inscribed on them (Shabbat 115b). Of the sample of amulets from late antiquity that have been found, the most interesting of them are demon bowls, pottery dishes painted with incantations and then buried under the door post of a house to trap underworld spirits who attempt to enter.
Beginning in the Middle Ages, amulets appear that are designed to protect against the Ayin Hara, the Evil Eye. Many more physical examples of amulets from the medieval period have survived, giving us a clearer picture of the forms, as well as the logic behind them. Many examples of silver, lead and pewter amulets have come down to us, so metal is apparently a preferred material for amulet making, though it may also be that metal's durability means more examples of these types of charms have survived. Sefer Reziel prescribes specific times on certain days when engraving amulets will make them potent.
With the advent of printing and modern stamping techniques, amulets were mass-produced in both metal and paper as pendants, small sheets, or broadsides. The most famous of these is the Middle Eastern tradition of the Shevviti talisman, using the words from Ps. 16:8 "I have placed the Eternal always before me."
More modern amulet makers will often use the same kind of animal skin parchment and ink that is used in making a Sefer Torah. These modern amulets feature either verses from Scripture with perceived apotropaic properties, or permutations of the names of God. Often these words and anagrams are arranged in magic circles, hexagrams, boxes, and other enclosed patterns (either to block out or trap the malevolent forces) to enhance their power. These also have mathematical associations, being grouped in threes, nines, or significant numbers.
Popular images appearing on amulets include the protective hand or chamsa, menorahs, fish, and angels. A few examples even have crude pictures of the very demonic forces the amulet is meant to ward off. One suspects the primitive quality of these demonic illustrations is deliberate, yet another way of degrading the power of the evil spirits, for many amulets are designed with attention given to aesthetics and are quite beautiful.
Beyond the materials used, there are rituals of power that must be observed when creating an amulet. Thus the maker will subject himself to a period of purification, usually three days, following the example of the Israelites who purified themselves for three days prior to receiving the Torah. Amulet-making manuals list prayers and incantations that must recited while constructing the kemia, along with those spells that will be written on it. Certain days and times are better for making amulets, and these are carefully observed. Until modern times amulets were generally regarded to be efficacious. Even today they enjoy widespread use in some traditional Jewish circles, especially among the Chasidic and Oriental (Asian and North African) communities. With few exceptions, notably in the writings of some Babylonian authorities and Maimonides, were widely accepted, or at least tolerated. Most controversies about their use arose not over their effectiveness, but about whether individuals were selling amulets with false claims, or over whether certain amulet designs may have originated in heretical circles, such as that of the false messiah, Shabbati Zevi.