Another is recited in the Yotzer ohr blessing and a third, the qiddusha de sedra (Jewish Babylonian Aramaic: קידושה דסדראַ, romanized: qiddúšā ḏ séḏrā, lit.
In the silent Amidah, it is a short prayer; in the repetition, which requires a minyan, it is considerably lengthier.
For the first verse, Isaiah 6:3, it is traditional for everyone to rise to their toes with each recitation of the word qaddosh (Hebrew: קָדוֹשׁ, lit. 'holy').
In the Mussaf service of Shabbat and festivals, a fourth verse is added: the opening line of the Shema.
Many sources describe the recitation of the Shema during Mussaf as a response to historical anti-Jewish decrees prohibiting reciting the Shema at the proper point of Jews’ religious service, but contemporary scholars have proposed a variety of other explanations, as well.
Moses Isserlis, recording the Ashkenazic practice, permits individuals to recite the kedushah without the Shulchan Aruch's recommendation in Orach Chaim 59:3.
[13] The first Biblical verse in the Kedushah, Isaiah 6:3, is also found in the Sanctus of some Christian liturgical ordinaries.