מְזוּזָה — מזוזה
memsheva zayin vavdagesh zayinqamats he: mezuzah, mezuza, mezzuzah, mezzuza
Hebrew: "doorpost" (plural "mezuzot" or "mezuzos")
Hear, O Israel: the Lord our God is one Lord: and thou shalt love the Lord thy God with all thine heart, and with all thy soul, and with all thy might. And these words, which I command thee this day, shall be in thine heart: And thou shalt teach them diligently unto thy children, and shalt talk of them when thou sittest in thine house, and when thou walkest by the way, and when thou liest down, and when thou risest up. And thou shalt bind them for a sign upon thine hand, and they shall be as frontlets between thine eyes. And thou shalt write them upon the posts of thy house, and on thy gates.
(Deuteronomy 6:4–9)
This passage of the Old Testament, known to Jews as the Shema or Sh'ma, is the basis of the mitzvah to attach mezuzot on the doorposts of a house. A small klaf (parchment from the skin of a kosher animal) has the Shema and Deuteronomy 11:13–21 handwritten in the STA'M script on one side and Shaddai, one of the names of God, on the other side. It is then carefully rolled from left to right, with the Shema on the inside so ha-Shem is facing out, and placed inside a small case, which sometimes has the letter shin (ש) on it.* arieh mentions that the scroll may also have כז במוכסז כז ("Cuzu B'mucsz Cuzu," a shifted form of ײ אלהינו ײ "YHVH Eloheinu YHVH") written on the ha-Shem side, but upside-down. A small ceremony is held, Chanukat haBayit, during which the case is attached to the right side of a doorpost or frame at an angle, top leaning towards the door.** Mezuzot may be attached with double-sided tape, glue, mortar, nails or screws, but not magnets or Velcro, and if it opens from the back, the back cover cannot be the only thing fixed to the frame (these rules are to ensure that the attachment is relatively permanent). Observant Jews will place a mezuzah on every doorframe in the house (except those leading to bathrooms or storage rooms), but often only one is placed at the front door. As one passes through a door with a mezuzah, the fingertips of the right hand touch the lips and then the mezuzah (some people touch the mezuzah first and then the lips).
Creating the scroll takes a lot of diligence. There can be no spelling errors, and the text must be neat enough that even a child can read it easily. A misshapen letter invalidates the scroll, as does an extra letter, a missing letter or even a stray inkblot. To ensure that the text is correctly written, the sofer recites the words of the text as sie writes it.
Depending on the scribe writing the text of the scroll and the quality of parchment, mezuzot can range greatly in price. Mezuzah Doctor (www.mezuzahdoctor.com) lists prices for scrolls ranging $36–$260, and you can see examples of other scrolls at http://www.safrus.com/mezuzah.html. Designs by Aliza has scroll cases for $30–$40.
Before the first mezuzah is affixed to a doorpost of a house, the following blessing is spoken:
בָּרוּךְ אַתָּה ײֳ אֱלׂהֵינוּ מֶלֶךְ הָעוֹלָם
אֲשֶר קִדְּשָׁנוּ בְּמִצְוֹתָיו וִצִוָּנוּ לִקְבּוֹעַ מְזוּזָה
Barukh atah Adonai, Elohaynu, melekh ha-olam
asher kid'shanu b'mitzvotav, v'tzivanu leek'boa mezuzah.
Blessed are You, our God, king of the universe
who has sanctified us with the commandments and commanded us to affix a mezuzah.
Once the mezuzah is in place, the Shehecheyanu blessing, said in times of happiness and new things (and on the first night of Chanukah), is spoken:
בָּרוּךְ אַתָּה ײֳ אֱלֹהֵינוּ מֶלֶךְ הָעו֗לָם
שֶׁהֶחֱיָנוּ וְקִיְּמָנוּ וְהִגִּיעָנוּ לַזְּמַן הַזֶּה
אָמֵן
Barukh atah Adonai, Elohaynu, melekh ha-olam
she-hecheeyanu, v'ki-y'manu, v'higianu, la-z'man ha-zeh
Blessed are You, our God, king of the universe,
for giving us life, for sustaining us, and for enabling us to reach this season.
Once the first mezuzah has been attached to the house and the approprate blessings recited, others may be affixed without more blessings.
A mechanically printed scroll does not fully satisfy the 423rd mitzvah. It must be hand-writted by a qualified sofer, and must have all 713 letters without a single misspelling. Mezuzot are to be checked twice every seven years by a qualified sofer, who checks the spelling and number of letters and looks for any damage to the klaf. If you move, you should take your mezuzot with you — if you leave them, the next owner of the house could show disrespect towards them, which is a grave sin. arieh says if you move and the new owners are Jewish, you are expected to leave them on.
This idea of placing religious text at the door of one's house is said to come directly from the Old Testament, but many scholars argue that the idea evolved from the ancient Egyptian practice of carving inscriptions on the doorposts of the home. In many parts of Europe until the 1800s, it was customary to embed the mezuzah inside the doorpost. In the Middle Ages, many people began adding the names of angels or religious symbols to their mezuzot, which Moses Maimonides argued against.
The mezuzah serves to remind all of the word of God. It consecrates the Jewish home, bringing another aspect of God to watch over the inhabitants and remind them of His presence. Kissing the fingertips and then touching it shows respect and love for God.
And finally, a second-hand true story about a mezuzah, from aish.com:
My wife's grandmother had developed a numbness in her hand. She visited a variety of doctors and specialists, but no one could help her. The numbness persisted for months, and was getting progressively worse.
Finally, my wife's grandmother asked her rabbi for advice. "Check your mezuzah," he said.
Left with no other "more practical" option, she took down the mezuzah and looked inside. The meticulously written scroll was perfect — except for one letter missing: a yud. Yud is related to the Hebrew word for hand, yad.
My wife's grandmother had the mezuzah replaced, and within days her hand returned to normal. True story.
* The ש also stands for שדי (Shaddai, sixth name given by Maimonides), which is either "[the One who] says 'enough'," indicating God's pleasure with the size of the world after He had finished creating it, or stands for shomer daltot Yisrael, "[God is] guardian of the doors of Israel."
** Rabbis couldn't decide whether the mezuzah should be placed horizontally or vertically, so they settled on tilting it at an angle.
I typed all the Hebrew in myself, and (being a goy and all) I'm not perfect, so there may be errors. If you notice any, please let me know!
References:
Judaism 101 Signs and Symbols: http://www.jewfaq.org/signs.htm
Kolel Reb on the Web: http://www.kolel.org/pages/reb_on_the_web/reb_on_the_web.html
Leo Rosten's The Joys of Yiddish (which everyone interested in Judaism or Jewish culture should read)
arieh — thanks!