The Temple in Jerusalem was where all divine values were revealed, and from it they flowed forth to the rest of the world. The Sanctuary (heikhal) was comprised of an entrance hall (ulam) and two chambers. The outer chamber, called the Holy (Kodesh), contained the menora (candelabrum), symbolizing wisdom; the shulḥan (table), symbolizing material sustenance and wealth; and the mizbaḥ ha-ketoret (incense altar), symbolizing prayer and the yearning to be close to God. The inner chamber, called the Holy of Holies (Kodesh Ha-kodashim), is where the basis of faith and Torah are revealed. In other words, it is there that the divine foundation of the Torah and the holiness of the congregation of Israel illuminate, and through their light, God animates the entire world. For this reason, the Kodesh Ha-kodashim housed the Ark of the Covenant, which contained the stone tablets (luḥot) that Moshe received at Mount Sinai and the Torah scroll he wrote. Atop the Ark was the kaporet (golden cover), with two cherubs rising from it, symbolizing the covenantal relationship and love between God and Israel. The location of the Kodesh Ha-kodashim within Jerusalem was atop the Foundation Stone (Even Ha-shetiya), which, our Sages tell us, was the rock from which the world was created (Yoma 54b). A parokhet (curtain) separated the Kodesh from the Kodesh Ha-kodashim, to demarcate different levels of holiness. For the sanctity of the Kodesh derives from that of the Kodesh Ha-kodashim. Without a separation, the light emanating from the Kodesh Ha-kodashim would have ascended directly to heaven, preventing it from radiating light and blessing to the Kodesh, and from there to the entire world.
Although people were not permitted to enter the Kodesh Ha-kodashim, nevertheless, by the light of the Shekhina (Divine Presence) which radiated from it, Israel and the whole world could return to God, correct their sins, and channel their prayers to God, as expressed in King Shlomo’s prayer at the Temple’s dedication. (See 1 Melakhim, ch. 8.)
Even after the Temple’s destruction and the ensuing exile, a trace of the Divine Presence never budged from the Kodesh Ha-kodashim. The longing and yearning of the Jewish people for the Divine Presence to dwell among them in Eretz Yisrael guarantees that the redemption will arrive. Then, God’s name will be sanctified over Israel, His people; Jerusalem, His city; Zion, the home of His glory; the kingship of the house of David, His anointed one; and His home, the Temple. God alone will rule over all His creations.
The location of the Kodesh Ha-kodashim is exalted so that no person may set foot there. Anyone who enters there is liable to death at the hands of heaven, as we read, “The Lord said to Moshe: Tell your brother Aharon that he is not to come at will into the Kodesh, beyond the parokhet, in front of the kaporet that is upon the Ark, lest he die; for I appear in the cloud over the kaporet” (Vayikra 16:2). The only person ever permitted to enter the Kodesh Ha-kodashim was the Kohen Gadol on the holy and awesome day of Yom Kippur. He would enter in a cloud of incense (section 7 below) to perform the day’s avoda (Temple service) on behalf of all Israel, as it is written, “Thus only shall Aharon enter the holy place” (ibid. v. 3). Over the course of Yom Kippur, the Kohen Gadol was required to enter the Kodesh Ha-kodashim four times. But entering a fifth time – even given his lofty position and the sanctity of Yom Kippur – would have made him liable to death at the hands of heaven (MT, Laws of Entering the Temple 2:4).