The Jewish Home
Not like Avraham who called [the Temple] "mountain," and not like Yitzhak who called it "field," but rather like Yaakov who called it "house"... (Talmud - Pesachim 88a)
Maimonides in the beginning of Hilchos Beis HaBechirah lists three functions of the Holy Temple in Jerusalem, the Beis Hamikdash:
(1) to be a bayis laHashem - literally, God's house; (2) to be the place where sacrifices will be offered; and (3) to be the place to which the Jewish people will ascend three times yearly to celebrate the festivals.
The Beis Hamikdash serves as a mountain (har), a place to ascend to, to look up to, a place that inspires one to feel that he is in the shadow of the Shechina, the Divine Presence. That is the function of the Beis Hamikdash emphasized by Avraham: Har Hashem yera'eh - "the mountain upon which God will be seen" and from which the Jewish people will be observed by God. This refers to the first Beis Hamikdash, on which the Shechina devolved and which made a profound impression on those who stood in its shadow.
Yitzchak emphasized the second function of the Beis Hamikdash by calling it a "field" (sadeh), a place for growth and development, an environment conducive to bringing out all man's various emotions and expressing them in God's service. This was the essence of the second Beis Hamikdash, which lacked the full measure of Shechina, but which still served as a place for prayer and the bringing of the sacrifices.
It was left to Yaakov, however, to perceive the all-encompassing nature of the Beis Hamikdash as the House of God. Yaakov clearly knew the place of the future Mikdash as one where his forefathers prayed. That is why he returned after having passed by on his way to Charan. Nevertheless after awakening from his dream, he exclaimed:
"...surely God is in this place and I did not know it.... How awesome is this place. This is none other than God's House, and this is the Gateway to Heaven." (Genesis 28:16-17)
Although he knew of the distinction of this site as a mountain and a field, its significance as a house, which he perceived at that moment, overshadowed either of those designations. That designation applies to the third Beis Hamikdash, which will be eternal and influence the entire world.
Yaakov perceived this aspect of the Beis Hamikdash as he was ready to descend into exile, where his children would be as the dust of the earth, trod upon by all the nations of the world, yet, at the same time, a source of inspiration and blessing to the entire world. In exile the concept of "God's House" would be embodied in the House of Prayer, House of Study, and the Jewish Home. These three would preserve the Jewish people in exile and enable them to return to Israel and receive the ultimate House of God, the third Temple.
To appreciate the precise function of the House of God, we must understand what a house is. A house is basically four walls, a door, and perhaps a window. The four walls serve three functions. First, they create an interior area, a private inner domain, separated from the public domain. The Jewish home must create an environment of Jewish values and morals, an inner sanctum of spirituality that serves as the foundation of Torah learning and observance.
Secondly, the walls form a partition that encompass and unite all the individuals who occupy this inner area. Peace in the home (shalom bayis) refers to the perfect harmony that the home engenders, where each individual feels himself part of a unit that must function together - each using their unique talents for a common goal.
And finally, the walls of the house serve as buffers against destructive foreign influences, hostile to Torah values.
Once the inner area is infused with sanctity and purpose, then the light from the inside can be projected from the windows, and the intense sanctity of this home environment can be exposed to the outside world
There are several Mitzvot that apply specifically to a house. The Mitzvah of Shabbos lights symbolizes the sanctity that the house must engender and the enlightenment of Torah values and ethics. In addition, the Shabbos lights symbolize the harmony that is produced when each member takes care not to step on others in the darkness of ignorance and selfishness.
The Mezuzah and ma'akeh (guardrail) represent the protection the house offers from the physical and spiritual dangers of the outside world. Checking for Chametz prior to Pesach teaches us that we must from time to time check to see if foreign influences have succeeded in invading the house and remove them.
Lastly, the Mitzvah of Chanukah lights placed outside the door or in the window symbolizes the influence that the Jewish home can have on the outside world.
The letters of the word bayis (house) itself hint to its function. The first letter, bais, represents bina, understanding - understanding of what to let in and what to keep outside. Yud is a letter of holiness, but it also represents the unity of all the separate integers that unite to form one unit of ten. The yud represents the holiness that pervades the home when all of the individuals unite in service of God with a common goal. And finally, the suf is a sign - a sign to the outside world of the Jewish home's influence on the entire world.
It is significant that the Parsha that depicts Yaakov's first exile deals primarily with our matriarchs. The woman is the essence of the house itself (Talmud - Shabbos 118b). To survive in exile and prepare for the Third Temple, we must strengthen our public houses, shuls, study houses, as well as our individual homes, to reflect the ultimate functions of that future house of God.