al-Wāḥid ibn Ismāʿīl ibn Aḥmad ibn Muḥammad al-Ruwayānī, al-Ṭabarī, the Shāfiʿī.
He was born at the end of the year 415 AH, and spent a period studying jurisprudence in Bukhara.
He heard ḥadith from Abū Manṣūr Muḥammad ibn ʿAbd al-Raḥmān al-Ṭabarī; Abū Ghānim Aḥmad ibn ʿAlī al-Kurāʿī al-Marwazī; ʿAbd al-Ṣamad ibn Abī Naṣr al-ʿĀṣimī al-Bukhārī; Abū Naṣr Aḥmad ibn Muḥammad al-Balkhī; Shaykh al-Islām Abū ʿUthmān al-Ṣābūnī; ʿAbd Allāh ibn Jaʿfar al-Khabbāzī; Abū Ḥafṣ ibn Masrūr; Abū Bakr ʿAbd al-Malik ibn ʿAbd al-ʿAzīz; Abū ʿAbd Allāh Muḥammad ibn Bayān the jurist; and several others.
He travelled in pursuit of both hadith and fiqh, excelled in jurisprudence, mastered it, engaged in debate, and produced splendid works.
Those who transmitted from him include Zāhir al-Shahhāmī, Ismāʿīl ibn Muḥammad al-Taymī, Abū Ṭāhir al-Silafī, Abū Rashīd Ismāʿīl ibn Ghānim, Abū al-Futūḥ al-Ṭāʾī, and many others.
He used to say, “Were the books of al-Shāfiʿī to be burned, I could dictate them all from memory.”
Among his writings are: al-Baḥr on the Shāfiʿī school—an exceedingly lengthy work, copious in benefits (1); Manāṣīṣ al-Shāfiʿī; Ḥilyat al-Muʾmin; and al-Kāfī.