Nissim ben Jacob
| Rav Nissim ben Jacob | |
|---|---|
| ניסים בן יעקב | |
| Title | Gaon | 
| Personal life | |
| Born | 990 | 
| Died | 1062 | 
| Parent | 
 | 
| Era | 10th-11th centuries | 
| Notable work(s) | Sefer mafteaḥ le-manʻ ūlei ha-talmūd, Siddur Tefillah, Sefer ha-Mitzvot, Hilkhot Lulav, Megillat Setarim, Sefer Ma'asiyyot ha-Hakhamim wehu Ḥibbur Yafeh meha-Yeshu'ah | 
| Known for | Talmudic commentary ha-Mafteach | 
| Other names | Nissim Gaon, רבנו נסים גאון | 
| Religious life | |
| Religion | Judaism | 
| Teachers | Chushiel, Jacob ben Nissim | 
| Senior posting | |
| Based in | Kairouan, Tunisia | 
| Students 
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Nissim ben Jacob (Hebrew: ניסים בן יעקב), also known as Nissim Gaon (Hebrew: רבנו נסים גאון, lit. 'Our teacher Nissim the Gaon'; 990–1062), was a rabbi and Gaon best known today for his Talmudic commentary ha-Mafteach, by which title he is also known.