YOẒEROT (Heb. pl. יוֹצְרוֹת, sing. יוֹצֵר, yoẓer), a series of piyyutim inserted in the benedictions which precede and follow the *Shema of the morning prayers. Yoẓer, the designation of the first piyyut (also called guf ha-yoẓer), came to refer to the series as a whole. The name is taken from the opening line of the first benediction before the Shema: Yoẓer or u-vore ḥoshekh etc…. ("Who createst light and formest darkness"). The yoẓer is considered one of the earliest forms of piyyut, though it is later than the kerovah. The first paytanim who composed yoẓerot were Eleazar b. Eleazar *Kallir and Joseph b. Nissan of Shaver Kiriathaim. Fragments of yoẓerot, however, were found in the Cairo Genizah and their literary structure testifies to their having been composed during "the period of the anonymous piyyut." This form of piyyut was widely known in Middle Eastern countries from the 9th to the 11th centuries. During this period 15 paytanim composed full series of yoẓerot for each of the weekly Torah portions. In Europe the yoẓer was also considered to be the acceptable form of piyyut. The yoẓerot series was initially intended to replace the established versions of the Shema blessings. With time, however, passages of the yoẓerot were integrated into the Shema. The series thus came to adorn the benedictions and all the other essential passages of the prayer, specifically: Ha-Kedushah de-Yoẓer and two verses from Shirat ha-Yam ("The Song of the Sea," Ex. 15:11 and 18) which were to be recited before Birkat ha-Ge'ullah.
The classical series of the yoẓerot consists of seven component parts: (1) The yoẓer or guf ha-yoẓer which concludes with the reciting of the first verse of the *Kedushah. (2) The ofan, the name being derived from the opening lines of the permanent prayer after which it was inserted. The ofan served as a bridge between the first and the second verse of the Kedushah. (3) Ha-me'orah, occasionally referred to in the Genizah as me'orot. It is named after the text of the concluding benediction, yoẓer ha-me'orot, and ends with the first benediction before the Shema. (4) The ahavah, taken from the second benediction before the Shema which immediately follows it (ha-boher be-ammo Yisrael be-ahavah) and with which it concludes. (5) The zulat, occasionally referred to as zulatkha in the Genizah (named after the conclusion of the standard verse of the prayer and inserted after it at a later period). In the Genizah, it also appears as emet, a title derived from the opening lines of the aforementioned text. It concludes with the first of the verses of Shirat ha-Yam; Mi kamokha. (6) Mikamokha which concludes with the second of the verses of the Shirat ha-Yam Adonai Yimlokh. (7) Adonai malkenu, named after the permanent text which, according to the Eastern ritual, is recited at this point. It ends with the benediction that concludes the Shema: Ga'al Yisrael. The last section was divided into two by the Eastern paytanim (9th to 11th centuries): Adonai malkenu and ve-ad matai. In Europe, the section is named after the concluding benediction: Ge'ullah. In the Eastern series, the yoẓerot for the regular Sabbath, and occasionally also those for the festivals, incorporate the opening section of the weekly reading or holiday portion into the body of the yoẓer; in the zulat, the haftarah. Around the tenth century, the Oriental paytanim introduced their yoẓerot with short opening piyyutim called maẓdar (introduction). In the ancient Ereẓ Israel ritual the yoẓerot for the morning prayers in which the Kedushah de-Yoẓer is not recited (on weekdays, including special weekdays such as Ḥanukkah, Purim, Rosh Ḥodesh, and ḥol ha-mo'ed, and on fast days) consisted only of five parts (without guf ha-yoẓer and the ofan). Among the components of the Oriental yoẓerot, only guf ha-yoẓer, ofan, and zulat are of any structural length; the other parts of the yoẓerot are short. In the European yoẓerot, all the component parts developed into separate and comprehensive piyyutim. In Spain the Mi kamokha was developed monumentally. The Italian and Ashkenazi (German) paytanim often omitted the me'orah, the ahavah, and the passages that follow the zulat from their series of yoẓerot. Several European paytanim composed segments of the yoẓerot for various occasions, without carefully integrating them into complete series.
Zunz, Poesie, 60–65: Elbogen, Gottesdienst, 210f.: M. Wallenstein, Some Unpublished Piyyutim from the Cairo Genizah (1956), 22–25.