The ancients believe that an amulet is supposedly charged with magical power that can ward off misadventure, disease, or the assaults of malign beings–whether demonic or human. A talisman is an object similarly used to enhance a person’s potentialities and fortunes. Amulets and talismans are two sides of the same coin. The former are designed to repels evil; the latter, to attracts blessing and prosperity. Historically, the mezuzah combines both features in rabbinic folklore and history.
The Mezuzah as an Amulet
Since Late Antiquity, our ancestors believed in mezuzah’s ability to supernaturally protect a Jew no matter where he or she happens to be. The mezuzah combines both the aspects of the amulet and talisman that we mentioned above. In one well-known Talmudic passage, we discover that some of the Sages believed that the biblical promise of a long life depends upon the observance of the mezuzah. As a proof text, the rabbis explain the verse “And you shall teach them your children … and you shalt write them upon the door posts of your house (mezuzot) … that your days may be multiplied and the days of your children” as a conditional promise. That is to say, if someone wants to enjoy a long life, then he had better be scrupulous in his observance of the mezuzah.
In another Talmudic passage, the King Artaban of Parthea one day sent a gift to Rabbi Judah. The gift was an exquisite and quite expensive pearl. The king’s only request was that the rabbi send a gift in return that was of equal value. Rabbi Judah sent the king a mezuzah. Artaban was displeased with the gift and came to confront the rabbi. “What is this? I sent you a priceless gift and you return this trifle?” The rabbi said, “Both objects are valuable, but they are very different. You sent me something that I have to guard, while I sent you something that will guard you.” 
Pagans Once Wore Phylacteries
As a side note, the meaning of the original Greek term φυλακτήριον ( “phylacteries”) a preservative or safeguard, an amulet: (cf. Demosthenes, p. 71, 24; Dioscorides (ca. 100 C.E.) 5, 158f (159f), and appears often in the writings of Plutarch. The ancient pagans believed that the wearing of phylacteries (as seen in some of the pictures of the goddess Ishtar), helped keep the evil spirits away. In all likelihood, ancient Jews were influenced by these pagan practices but later came to redefine their religious significance in light of Judaism’s sacred teachings. Archaeologists discovered these boxes in the caves of Murabbaat, which further confirms literary evidence of the ritual practice existing sometime in the century preceding the Common Era. Whether the members of Qumran actually wore such things is by no means clear. It is possible certain Pharisees who joined this sect, brought them with them to Qumran.
Fortunately, no Jew calls tefillin “phylacteries” today–but in the days when Jews spoke Greek, they called tefillin by a different name.
The Ancients Lived in a Demon Haunted World
The ancients believed that they lived in a demon-haunted world. They probably had good reasons to do so. The average human lifespan was dramatically less than what we now enjoy. Infant mortality probably resembled what it presently in the Third World countries. Yes, the world was a much more of a dangerous place. The belief in demons seemed only natural and even logically plausible to the pre-modern mind. Despite the advancements made in science and technology, we often find ourselves unconsciously believing in the protective power of these ancient tools. If for nothing else, they serve as psychological props for people undergoing psychological difficulties in their lives. Seeing a mezuzah on a door offers a feeling of protection.
Given what the ancients had to work with, it is only fitting we judge charitably when evaluating their belief systems. However, we have every right to expect more from our modern rabbinic scholars–especially in light of Jewish rational thought as championed by Maimonides and Gersonides (ca. 14th century). Even in the Israeli news media, rabbis boldly promote the use of the mezuzah as an amulet as though we are still living in the Dark Ages.
Recent Popularizations of the Mezuzah as Amulet
As I was preparing a class on amulets in Jewish history and folklore, I came across an interesting letter written by the late Lubavitcher Rebbe that stressed the importance of the mezuzah as a spiritual device capable of warding off the effects of the evil eye and other potential tragedies. The late Rebbe writes: “Moreover, this protection embraces the members of the household also when they go out of the house, as it is written, ‘G-d will guard your going and your coming from now and forever.’ It is further explained in our holy sources that the Divine Name (Shin-Dalet-Yud) written on the back of the sacred Mezuzah parchment spells out the words, “Shomer Dalsos Yisroel–Guardian of Jewish Doors.” Let it also be remembered that inasmuch as all Jews constitute one body, and are bound up with one another, every Mezuzah is a Divine protection not only for the individual home, with everybody and everything in it, but each additional kosher Mezuzah that is affixed on a doorpost of any Jewish home, anywhere, adds to the protection of all our people everywhere.” 
Perhaps more than any modern scholar of his time, Rabbi Schneerson implicitly suggests that God will allow tragedy to strike anyone who fails to observe this important biblical precept. 
Now, in fairness to Rabbi Schneerson, his belief in the efficacy of mezuzot actually has strong antecedents in Jewish history. In fact, there are several rabbinic stories attesting to its alleged protective power in superstition and folklore. Rabbis like Schneerson, Ovadiah Yosef, Mordechai Gifter and countless others, frequently blame terrorist attacks in Israel on the murdered victims’ failure to maintain “kosher” mezuzot.
How comforting …
Beware of the Unkosher Mezuzah!
Numerous other rabbinic statements both of the rabbinic and medieval literature certainly re-enforces the idea that the mezuzah protects a Jew or even a gentile that has it on the doorpost of his property. Of course, the Kabbalah went to even greater lengths in explaining why the mezuzah protects the home. According to the Zohar, the word mezuzot is composed of two words, zaz mavet, “death departs,” as proof positive why every room in a house should be guarded by a mezuzah. (Incidentally, this etymology is linguistically spurious.) Another well-known interpretation reads, “R. Abba said, ‘In how many ways does the Blessed Holy One show His loving-kindness to His people! When a man builds a house; the Blessed Holy One says to him: ‘Write My Name and put it upon your door (mezuzah), and thou wilt sit inside your house and I will sit outside thy door and protect you!’” (Zohar 2:36).
Historian and Rabbi Joshua Tractenburg noted that during the Middle Ages, whenever a community was ravaged by plague, “The leaders inspected the mezuzot on the doorposts to discover which was improperly written and therefore responsible for the visitation. The mezuzah has even come off the doorposts; during the World War many of the Jewish soldiers carried mezuzot in their pockets to deflect enemy bullets; it has today become a popular watch-charm among Jews. I have even been told of a nun who dropped her purse one day, and among its contents, scattered on the ground, was—a mezuzah!”
My father, like many secular Jews, always kept a mezuzah in his car. Despite our civility and science, we are a superstitious people.
Tractenburg’s musing is similar to a popular Chabad miracle story about how the Lubavitcher Rebbe once healed a hunchback when he realized that the man’s mezuzah was unkosher because the word “walk” was misshaped!
Something to Think About . . .
Modern Jews living in the 21st century really ought to question what kind of Supreme Being will cause people to suffer just because some scribe made a mistake in writing a mezuzah? Logically, if anyone deserves punishment, shouldn’t it be the scribe? In God’s governance of the world, surely justice demands that a punishment fit the crime that was perpetrated, but what kind of Deity would punish some poor schlemiel just because of a typo found in a mezuzah?
It is no wonder why so many Jews across all denominations find it hard to relate to such a vindictive image of God. The God of retribution may inspire fear, but cannot inspire a sense of security and healthy relatedness. Michael Shevack and Rabbi Jack Bemporad cleverly dubs this theological view of God as the “Marquis de God.”
Wanted: Dominant deity for submissive person–must be into pain and bondage. Willing to inflict human suffering in pursuit of satisfaction—humiliation technique is a plus. Sense of humor not required. Inquire P.O. Box G.O.D . . . Get out the whips, the chains, the earthquakes and pestilence. It’s time for some good old-fashioned fun with a good old-fashioned god. Yes, this is the proverbial god of wrath—the Marquis de God—ready to show you how much he cares by punishing you. For the Marquis de God is simply a god who hates. This is a deity who despises sins and sinners with such a passion that he’ll murder in order to exterminate them. He forces his noblest creation to dance like a trained poodle on the brink of annihilation.”
While it is true our ancestors believed a mezuzah was an amulet and a talisman, we must reject such thinking because it is out of line with how we now experience the modern world. Think about it . . . When the Protestant theologian and philosopher Jonathan Edwards (who is no relation to N.C. Senator John Edwards) wrote his 1741 classic, “Sinners in the Hand of An Angry God,” the revivalist theologian used pretty lurid imagery to keep his followers along the straight and narrow. Ask yourself: Why would you ever want to pray to a God who is only all too willing to hurt you if you don’t have a kosher scroll on the doorpost of your home? If such a God existed, He would be a Tyrant. Belief in a cruel God can lead to atheism and cynicism.
In short, the images of a God Who is always ready to pounce on sinners for failing to keep a “kosher” mezuzah is a wrongheaded theological attitude that all of us ought to reject. Such a belief system is not much different than the kind of theological ideas that are routinely spewed from the mouth of Pat Robertson. We need to adopt a more rational approach to mysticism, one that leaves the ashes of old discarded superstitious ideas buried in the past–where they belong–and not in the present.
 Jerusalem Post, May 16, 1996.
 BT Talmud Shabbat 32a, the failure to observe the mezuzah can result in tragedy (Rashi).
 JT Peah 1:1; 15d.
 Letters of the Lubavitcher Rebbe
 In one Chabad publication, Alexander Poltorak’s “The Protective Power of Mezuzah,” the author writes, “In one of the Rebbe’s letters, he recommends to his correspondent, who complained of nightmares, to keep a kosher mezuzah near her bed. To another correspondent suffering from migraines, the Rebbe suggested that she keep a kosher mezuzah wrapped in a cloth with her at all times (besides Shabbath when carrying outside is prohibited) promising that it would improve her health. It is easily understood that a non-kosher mezuzah does not possess any protective qualities. Therefore when, G‑d forbid, someone is sick or some other misfortune befalls, the very first thing (after calling 911) is to check the mezuzoth in the house. This has been Jewish custom from time immemorial. If some of the mezuzoth turn out to be non-kosher or their status is in doubt, they should immediately be fixed if possible, or replaced by new kosher mezuzoth. Countless stories are told and retold in Jewish folklore about people who became well, regained lost jobs, and about barren women who became mothers, after fixing or replacing non-kosher mezuzoth. Some of these stories have been documented and published.
 BT Avodah Zarah 11a
 Joshua Tractenberg, “Jewish Magic and Superstition: A Study in Jewish Folk Religion” (New York: Berhman House, 1939), 146