The Musaf service of Yom Kippur is similar in structure to the Musaf prayers of other holidays, except that it includes many additional liturgical compositions and Selihot, particularly in the prayer leader’s repetition. The confession is recited once again at the conclusion of the individual Amida prayer and during the cantor’s repetition.

During the middle blessing of the prayer leader’s repetition of the Amida prayer, the entire congregation recites, along with the prayer leader, the Aleinu prayer, which is a prayer recited every day at the conclusion of the three daily prayer services. It consists of praise to God and is followed in the Yom Kippur Musaf service by a liturgical composition describing the Temple service on Yom Kippur. This composition contains a historical account beginning with Adam and his sin, through the forefathers, and to Aaron the first High Priest. It then details the different stages of the Temple service performed by the High Priest in the Temple.

Further reading: For a description of the High Priest’s service in the Temple on Yom Kippur, see A Concise Guide to the Torah, p. 293.

During the Aleinu prayer, upon reaching the words “and we bow and prostrate ourselves” (ואנחנו כורעים ומשתחווים), and also during the description of how all assembled in the Temple would bow upon hearing the High Priest utter the name of God during the Temple service, it is customary for all those praying in the synagogue to bow down on the floor. Since it is prohibited to bow on a stone floor outside of the Temple, it is customary to spread a towel or cloth to separate between the floor and one’s knees and forehead. It is recommended to prepare in advance by bringing something from home to use for this purpose.

In many congregations there is a break between the morning [Shaharit] and Musaf services and the afternoon [Minha] and concluding [Ne’ila] prayers. Many worshippers return to their homes during this time, which is meant to allow for people to rest a bit and to be able to return to the synagogue with renewed energy. However, in some congregations the prayers are conducted without any break, and worshippers remain in the synagogue for the entire day.