NISSI (Nissim) BEN BERECHIAH AL-NAHRAWANI (late ninth–early tenth century), head of the *kallah and poet in Babylon. Nissi appears to have come from Nahrawan in Persia. *Nathan ha-Bavli relates (Neubauer, Chronicles 2 (1895), 29–80) that when the Exilarch David b. *Zakkai was embroiled with the head of the Pumbedita Academy Rav *Kohen Ẓedek – in fact, the person involved was Mubashir b. Rav Kimoi *ha-Kohen and not Rav Kohen Ẓedek – it was Nissi, Resh Kallah in the Sura Academy, who succeeded in 922 in making peace between the disputants. Nathan ha-Bavli relates there that Nissi was noda be-nissim (i.e., a doer of miraculous deeds). In 928 when the question of appointing a gaon in the Sura Academy came up, this post was offered to him by *David b. Zakkai, but he refused it because of his blindness. Zemaḥ ibn Shahin and Saadiah b. Josef *Alfayumi competed for this post and despite the recommendation of Nissi that Ẓemaḥ ibn Shahin be appointed, the Exilarch appointed Saadiah to the gaonate. Nissi was one of the most important and fruitful of the paytanim of his country. In the Cairo Genizah, and also in other sources, poems and piyyutim by him were preserved, of which only a few have been published. Well known is his confession for the Day of Atonement, beginning: "Lord of the Universe, before all else, I have no mouth to answer," which has been adopted into many rites and republished hundreds of times. However, only with the discovery of the Genizah did the true identity of its author become clear.
B. Halper, in: Ha-Tekufah, 20 (1923), 272–4; Davidson, Oẓar, 4 (1933), 452; J. Mann, in: Tarbiz, 5 (1934), 154f., 160; S. Bernstein, in: Bitzaron, 36 (1957), 156–64; J. Schirmann, Shirim Ḥadashim min ha-Genizah (1965), 23–28; A.M. Habermann, Toledot ha-Piyyut ve-ha-Shirah (1920), 100–4.