- Jawharat al-tawḥīd (Laqānī, Ibrāhīm ibn Ibrāhīm)1
- Jawī Zādah, Muḥammad ibn Ilyās, -1547 or 1548. Risālah fī al-masḥ ʻalá al-khuffayn1
- Jaʻbarī, Arslān ibn Yaʻqūb, -1300. Risālat al-tawḥīd1
- Jurjānī, ʻAlī ibn Muḥammad, al-Sayyid al-Sharīf, 1340-14131
- Jurjānī, ʻAlī ibn Muḥammad, al-Sayyid al-Sharīf, 1340-1413. Ḥāshiyah ʻalá Maṭāliʻ al-anwār1
- Jāmī, 1414-1492. Risālah-i muʻammā1
- Jāmī, 1414-1492. Tafsīr al-fātiḥah al-sharīfah1
- Jīlī, ʻAbd al-Karīm ibn Ibrāhīm, 1365 or 1366- Insān al-kāmil fī maʻrifat al-awākhir wa-al-awāʼil1
- Khamrīyah (Ibn al-Fāriḍ, ʻUmar ibn ʻAlī)1
- Khūjahʹzādah, ʻAbd al-Naṣīr ibn ʻAbd Allāh, active 16th century. Taḥrīrāt ʻalá al-Ṭarīqah al-Muḥammadīyah1
- Knowledge, Theory of (Islam)1
- Kufr (Islam)1
- Kumayl ibn Ziyād, 633 or 634-7011
- Language and languages--Style1
- Liquor laws (Islamic law)1
- Love--Philosophy1
- Magic squares1
- Mahdi1
- Malikites1
- Maqṣūrah (Ibn Durayd, Muḥammad ibn al-Ḥasan)1