Ishaq ibn Mansur al-Kusaj
- Died
- 251 AH
- Born in
- Merv
Ishaq ibn Mansur al-Kusaj (c. after 170–251 AH / c. after 786–865 CE) was a Hadith transmitter and jurist from Merv who settled in Nishapur, celebrated for recording the legal and doctrinal responsa of Ahmad ibn Hanbal and Ishaq ibn Rahwayh in his compilation Masa'il al-Imam Ahmad wa-Ishaq ibn Rahwayh (The Inquiries of Imam Ahmad and Ishaq ibn Rahwayh).
Lineage and Early Life
He was Abu Ya'qub Ishaq ibn Mansur ibn Bahram al-Tamimi al-Marwazi. The sobriquet al-Kusaj is an Arabicized Persian term denoting an individual who has no facial hair on the sides of his cheeks. He was born in Merv after 170 AH and grew up in Nishapur.
Education and Scholarly Activity
In pursuit of religious knowledge, he traveled extensively across Iraq, the Hijaz, and the Levant. He studied and transmitted hadith from prominent scholars of his era, including Sufyan ibn 'Uyayna, Yahya ibn Sa'id al-Qattan, 'Abd al-Rahman ibn Mahdi, Waki' ibn al-Jarrah, Abu Usama, al-Nadr ibn Shumayl, 'Abd al-Razzaq al-San'ani, Rawh ibn 'Ubada, and Abu al-Yaman al-Hakam ibn Nafi'. He studied jurisprudence under Ahmad ibn Hanbal, Ishaq ibn Rahwayh, and Yahya ibn Ma'in, gathering their rulings and doctrinal positions.
A well-known incident illustrates his dedication to legal verification: upon hearing a rumor that Ahmad ibn Hanbal had recanted certain legal positions he had recorded from him, Ishaq ibn Mansur packed the manuscripts into a leather sack, carried it on his back, and journeyed on foot to Baghdad. There, he presented each written response to Ahmad, who reaffirmed his rulings and expressed admiration for his rigorous diligence.
He taught and narrated hadith in Baghdad and Nishapur. A distinguished group of traditionists transmitted from him, including Muhammad ibn Isma'il al-Bukhari, Muslim ibn al-Hajjaj, Abu 'Isa al-Tirmidhi, al-Nasa'i, Ibn Majah, Abu Dawud al-Sijistani, Abu Zur'a al-Razi, Abu Hatim al-Razi, Ibn Khuzayma, Ibrahim al-Harbi, and 'Abd Allah ibn Ahmad ibn Hanbal.
Scholarly Standing
He was widely recognized as a trustworthy hadith master and jurist. When asked about him, Muslim ibn al-Hajjaj characterized him as trustworthy and reliable (thiqah ma'mun). Al-Nasa'i described him as a trustworthy scholar from Merv (marwazi thiqah). Abu Hatim al-Razi affirmed his reliability by designating him as truthful (saduq).
Death
Ishaq ibn Mansur made his permanent residence in Nishapur, where he died in 251 AH. According to al-Husayn ibn Muhammad al-Qabbani, he died on a Thursday and was buried on Friday, with ten days remaining in Jumada al-Ula 251 AH. Another report states that he died on a Monday and was buried on Tuesday, after ten days had elapsed in Jumada al-Ula of the same year.
Answer updated
List of Works
A 3rd-century AH legal compilation, this work systematically documents legal rulings and doctrinal positions solicited from Ahmad ibn Hanbal and Ishaq ibn Rahwayh. Organized across standard legal chapters, it serves as an early primary record of early comparative jurisprudence and the jurisprudence of the traditionists (ashab al-hadith), preserving queries, points of agreement and divergence between both authorities, and dialectical discussions on legal rulings and textual evidence.