The Musaf prayer recited on Shabbat is especially significant and distinct from other prayers. One of the prominent features of this prayer is the special Kedusha of "Keter" which is recited as part of Musaf. Ashkenazim do not recite this Kedusha, following the view that it is improper to recite such a lofty prayer in our condition of exile. Sepharadim, however, indeed recite "Keter."
In the introductory passage of this prayer, we proclaim that we will recite "Kadosh Kadosh Kadosh" together with the heavenly angels ("Yahad Kulam Kedusha Lecha Yeshaleshu"), and we then proceed to recite "Kadosh Kadosh Kadosh." A number of commentators raised the question of how to reconcile this proclamation with the Gemara’s comment in Masechet Hulin that the angels do not recite Kedusha in the heavens until after the Jewish People recite it here in this world. How can we proclaim that we recite Kedusha together with the angels, if they are not permitted to recite it until after we do?
The Aruch Ha’shulhan (Rav Yechiel Michel Epstein of Nevarduk, 1829-1908) answered, quite simply, that once we recite Kedusha during Shaharit, the angels are then permitted to recite Kedusha, and we recite it together with them at Musaf. The recitation of "Keter" at Musaf thus marks a very significant and sacred moment, when we join together with the heavenly angels for the purpose of declaring Hashem’s sanctity.
Later in "Keter," we recite, "Ayeh Mekom Kebodo" ("Where is the place of His majesty?"). It is written in some editions of the Siddur that at the point, when we recite these words, we receive an additional dimension to the special soul of Shabbat ("Tosefet Neshama"). For this reason, some people have the practice of elongating the pronunciation of these words so they can have in mind that they receive this addition to their souls. Some have suggested that this phrase is alluded to in the verse in the Ten Commandments, "Zachor Et Yom Ha’Shabbat Le’kadesho" ("Remember the day of Shabbat, to make it sacred"), as the first letters of "Et Yom Ha’Shabbat" spell the word "Ayeh."
In the Kedusha of "Keter" we also recite the verse, "Shema Yisrael Hashem Elokenu Hashem Ehad." The inclusion of this verse in "Keter" dates back to the time when the authorities forbade the Jews to recite "Shema," recognizing the profound importance and power of this recitation. The Jews responded by "hiding" the recitation of "Shema" in "Keter," and this practice continued even after the ban was lifted.
Following "Shema Yisrael," we declare, "Hu Elokenu Hu Abinu Hu Malkenu Hu Moshi’enu" – "He is our G-d, He is our Father, He is our King, He is our Savior…" We first avow our acceptance of His rule ("He is our G-d"), and then acknowledge that He is our "Father" and thus, like any father, wants only the best for us. But unlike ordinary fathers, G-d is also "our King" and has unlimited resources and capabilities. As such, we ask and pray that "Hu Moshi’enu" – He save us from our current exile just as He saved us from the Egyptian bondage ("Aharit Ke’reshit").
This prayer for redemption is a testament to the special sacred quality of the Shabbat Musaf prayer, which is an opportune time to pray for our nation’s final redemption. For this reason, we recite in the Musaf prayer, "Yehi Rason…She’ta’alenu Le’arsenu…Ve’sham Na’aseh Lefanecha Et Korbenot Hovotenu" – praying that G-d return us to the Land of Israel and rebuild the Mikdash so we can once again offer our sacrifices.
