What is Inside the Mezuzah?
(ד) שְׁמַ֖ע יִשְׂרָאֵ֑ל ה' אֱלֹקֵ֖ינוּ ה' ׀ אֶחָֽד׃ (ה) וְאָ֣הַבְתָּ֔ אֵ֖ת ה' אֱלֹקֶ֑יךָ בְּכָל־לְבָבְךָ֥ וּבְכָל־נַפְשְׁךָ֖ וּבְכָל־מְאֹדֶֽךָ׃ (ו) וְהָי֞וּ הַדְּבָרִ֣ים הָאֵ֗לֶּה אֲשֶׁ֨ר אָנֹכִ֧י מְצַוְּךָ֛ הַיּ֖וֹם עַל־לְבָבֶֽךָ׃ (ז) וְשִׁנַּנְתָּ֣ם לְבָנֶ֔יךָ וְדִבַּרְתָּ֖ בָּ֑ם בְּשִׁבְתְּךָ֤ בְּבֵיתֶ֙ךָ֙ וּבְלֶכְתְּךָ֣ בַדֶּ֔רֶךְ וּֽבְשָׁכְבְּךָ֖ וּבְקוּמֶֽךָ׃ (ח) וּקְשַׁרְתָּ֥ם לְא֖וֹת עַל־יָדֶ֑ךָ וְהָי֥וּ לְטֹטָפֹ֖ת בֵּ֥ין עֵינֶֽיךָ׃ (ט) וּכְתַבְתָּ֛ם עַל־מְזוּזֹ֥ת בֵּיתֶ֖ךָ וּבִשְׁעָרֶֽיךָ׃ (ס)
(4) Hear, O Israel! Adonai our God, Adonai is One. (5) You shall love Adonai your God with all your heart and with all your soul and with all your might. (6) Take to heart these instructions with which I charge you this day. (7) Impress them upon your children. Recite them when you stay at home and when you are away, when you lie down and when you get up. (8) Bind them as a sign on your hand and let them serve as a symbol on your forehead; (9) inscribe them on the doorposts of your house and on your gates.
(13) If, then, you obey the commandments that I enjoin upon you this day, loving Adonai your God and serving God with all your heart and soul, (14) I will grant the rain for your land in season, the early rain and the late. You shall gather in your new grain and wine and oil— (15) I will also provide grass in the fields for your cattle—and thus you shall eat your fill. (16) Take care not to be lured away to serve other gods and bow to them. (17) For the Adonai’s anger will flare up against you, and God will shut up the skies so that there will be no rain and the ground will not yield its produce; and you will soon perish from the good land that Adonai is assigning to you. (18) Therefore impress these My words upon your very heart: bind them as a sign on your hand and let them serve as a symbol on your forehead, (19) and teach them to your children—reciting them when you stay at home and when you are away, when you lie down and when you get up; (20) and inscribe them on the doorposts of your house and on your gates— (21) to the end that you and your children may endure, in the land that Adonai swore to your fathers to assign to them, as long as there is a heaven over the earth.
How Do You Hang the Mezuzah?
How to Affix a Mezuzah from Blu Greenberg in How to Run a Traditional Jewish Household
A mezuzah should be fixed to the doorpost of every living space in the house, not just the entrance door. Any room that has two doorposts and an overhead lintel requires a mezuzah, so one should check with a rabbi. Bathrooms, closets, laundry room, boiler room, and so forth, however, do not require a mezuzah...
The mezuzah is affixed to the right side of the door as one enters a room. In other words, if your door swings open from hallway into bedroom, the mezuzah would be nailed to the right-hand doorpost as your face the bedroom from the hall. This is so no matter whether the doorknob is on the right- or left-hand side. It should be placed at the lower part of the top third of the doorpost, which is generally about eyeball height for a six-foot-tall person. It is affixed at a slant, with the lower part of the container toward you as you face the right doorpost.
A mezuzah contains God’s name and therefore great pains are taken to see that it doesn’t fall. The case must be securely attached at top and bottom rather than hanging by a nail from the top of the mezuzah. If the doorpost is too narrow to affix the mezuzah on a slant, it can be attached vertically, but still must be nailed or glued at top and bottom.
(א) בִּרְכַּת הַמְזוּזָה
(ב) הקובע מזוזה מברך:
(ג) בָּרוּךְ אַתָּה ה' אֱלֹקֵינוּ מֶלֶךְ הָעוֹלָם, אֲשֶׁר קִדְּשָׁנוּ בְּמִצְוֹתָיו וְצִוָּנוּ לִקְבֹּעַ מְזוּזָה:
Blessed are You Adonai our God, ruler of the universe, who makes us holy with commandments and commands us to affix a mezzuzah.
Barukh ata Eloheinu melekh ha-olam, asher kid-shanu be-mitzvotav ve-tzivanu likboa mezuzah.