- Italy--Umbria1
- Italy--Veneto1
- Italy--Vicenza1
- Italy--Villanova Monteleone1
- Izmīrī, Muṣṭafá ibn Rajab, active 17th century1
- Iṣbāḥ1
- Iṣfahānī, Maḥmūd ibn ʻAbd al-Raḥmān, 1275 or 1276-1348 or 1349. Tasdīd al-ʻaqāʾid fī sharḥ Tajrīd al-qawāʻid1
- Jabbārīyah1
- Jagadīśatarkālaṅkara. Vyādhikaraṇa1
- Jaghmīnī, Maḥmūd ibn Muḥammad, -1221?1
- Jahmīyah1
- Jaina cosmology1
- Jaina hymns, Prakrit1
- Jaina literature, Sanskrit1
- Jaina mythology1
- Jaina philosophy1
- Jainism--Doctrines1
- Jalāl al-Dīn Rūmī, Maulana, 1207-12731
- James, the Greater, Saint1
- Jammāʻīlī, ʻAbd al-Ghanī ibn ʻAbd al-Wāḥid, 1146-12031