Author
- Inayat Khan1
- Isaac Lopez1
- Isaac Luria1
- Isaac Sasportas1
- Isaac of Troki1
- Ismāʻīl ibn Muḥammad Māzandarānī1
- Israel Alnaqua1
- Israel Yaakov Algazi1
- Jacob Meyer1
- Jacob ben Reuben ibn Zur1
- Jaghmini1
- Jai Singh II1
- Jalal al-Din Mohammad Tabrizi1
- Jalaluddin al-Mahalli1
- Jamāl al-Dīn Khvānsārī1
- Jaʻfar Astarābādī1
- Jews1
- John Chrysostom1
- Juan Vicente de Güemes, 2nd Count of Revillagigedo1
- Juana I of Castile1