- Geography, Arab4
- God (Islam)--Proof4
- God (Islam)--Worship and love4
- Hair--Religious aspects--Islam4
- Ibn Bābawayh al-Qummī, Muḥammad ibn ʻAlī, 918 or 919-991 or 992. Man lā yaḥḍuruhu al-faqīh4
- Ibn Malak, ʻAbd al-Laṭīf ibn ʻAbd al-ʻAzīz. Sharḥ Manār al-anwār fī uṣūl al-fiqh4
- Ibn Wahbān, ʻAbd al-Wahhāb ibn Aḥmad, d. 1366 or 7. Qayd al-sharāʼid4
- Ibn al-Sāʻātī, Aḥmad ibn ʻAlī, 1254-1294 or 5. Majmaʻ al-baḥrayn wa-multaqá al-nayyirayn4
- Ijtihād (Islamic law)4
- Imamate4
- Indonesia--Java4
- Intention--Religious aspects--Islam4
- Interest (Islamic law)4
- Iran--Tabrīz4
- Isfarāyīnī, Muḥammad ibn Muḥammad, d. 1285. Ḍawʼ ʻalá al-Miṣbāḥ4
- Islam and philosophy4
- Islamic interpretations of Adam4
- Istiṣḥāb (Islamic law)4
- Kings and rulers--Duties4
- Laylat al-Qadr4