When Meies Matz affixed the mezuzah to the doorpost of her Berkeley home last month, a year after her conversion to Judaism, she felt she had finally come home.

Twenty-five guests gathered as Matz, husband David and their three children hung eight mezuzot throughout their gray stucco home. Among the celebrants was Rabbi Eliezer Finkelman of the family's Orthodox Berkeley synagogue, Congregation Beth Israel.

"We had [mezuzot] posted in our previous home before my conversion," Matz said. "But now I really felt I had the support of my community.

"It made me feel more connected than I ever have before."

The commandment to affix mezuzot upon the doorposts is one of many that bind the Jewish people together, according to Rabbi Eliahu Shalom Ezran of San Francisco's Congregation Magain David Sephardim. The practice signifies that "we, as Jews, are in compliance with our heritage."

Ever since Moses stood on Mount Sinai, Jews have heeded Deuteronomy by showing a commitment to honoring the words of the faith: "You shall inscribe them on the doorposts of your house and on your gates" (Deut. 6:4-7).

In "How to Run a Traditional Jewish Household," author Blu Greenberg writes that the mezuzah draws significance not only from its contents — a small scroll inscribed with the two paragraphs of the Sh'ma, affirming the covenant between God and the Jewish people — but also from its container.

This tiny receptacle marks a home as Jewish, and keeps its residents aware that they are custodians of the commandments.

"The mezuzah is something to remind us that we have a gift, and the gift is the Torah," said Matz.

Viewed as a sacred object and treated with reverence, the mezuzah serves as a reminder of God's presence. It is often kissed as a mark of respect, usually by lightly touching it with two fingertips and then briskly touching one's lips, as Harvey Lutske writes in "The Book of Jewish Customs."

Some, when passing the mezuzah, recite this verse from Psalms: "May God protect my going out and coming in, now and forever."

Some Bay Area rabbis maintain that the mezuzah forms a symbolic barrier between the public and private spheres, marking the home as holy.

"It serves as a reminder to be grateful for the home and for those that live within," said Rabbi Helen Cohn of San Francisco's Congregation Emanu-El.

Rabbi Sheldon Lewis of Congregation Kol Emeth in Palo Alto agrees. The mezuzah, he said, is "a reminder of the potentiality of creating a sacred space in one's home, while testifying to the community" that the householders have "a personal relationship with God."

While some rabbis believe the mezuzah has mystical powers, others maintain that its role is primarily educational. When Rabbi Ted Alexander of San Francisco's Congregation B'nai Emunah leaves his house, he touches the mezuzah — the gesture, he says, reminds him to behave as well in the outside world as he expects himself to behave at home.

However, he does not kiss the mezuzah, emphasizing that one should place a greater emphasis on revering the words rather than their container: "A little less Torah kissing, a little more Torah observing," he said.

To kiss or not to kiss is not the only conundrum. The mitzvah of posting mezuzot carries its own series of protocols, regulating how a mezuzah should be placed, how it is blessed and other details.

Why is the mezuzah affixed at a slant? Opinions vary, but some say the custom began as a compromise. According to Lutske, the 12th-century scholar Rashi argued about this issue with his grandson, Rabbenu Tam. Rashi believed the mezuzah should hang vertically, while Rabbenu Tam insisted on horizontal placement.

With a bit of negotiation, the mezuzah was posted obliquely and angled inward, a placement that is now customary.

In order to be kosher, the mezuzah's klaf, or inscription, must be written by a scribe in ink on parchment. (Printed or photocopied scrolls are not considered kosher.) The parchment is rolled so that when it is opened and checked twice every seven years, the name Shadai appears on the back. This is an acronym for Shomer Dalot Yisrael, which means "The Guardian of the Doors of Israel," signifying that God will watch our doors to protect us from harm.

According to Greenberg, when the mezuzah is affirmed as kosher, the worshipper holds it in one hand and recites this prayer:

"Baruch ata Adonai Elohainu melech ha-olam asher kidshanu b'mitzvotav v'tzivanu likboa mezuzah."

As Matz recited those words and posted her own mezuzot, she felt a deep connection to the Jewish people.

"Now it feels like home," she said.