—an ally of the Ansar, he fought at the Battle of the Trench and at other engagements.

Abu Yusuf was born in 113 AH.

He narrated hadith from Hisham ibn ʿUrwah, Yahya ibn Saʿid al-Ansari, ʿAtaʾ ibn al-Saʾib, Yazid ibn Abi Ziyad, Abu Ishaq al-Shaybani, ʿUbayd Allah ibn ʿUmar, al-Aʿmash, Hajjaj ibn Artat, and from Abu Hanifa. He remained in Abu Hanifa’s company, studied law under him, and was the most eminent and knowledgeable of his pupils. Through Abu Yusuf scholars such as Muhammad ibn al-Hasan, Muʿalla ibn Mansur, Hilal al-Raʾy, Ibn Samaʿah, and others received their training.

Those who transmitted from Abu Yusuf include Yahya ibn Maʿin, Ahmad ibn Hanbal, ʿAli ibn al-Jaʿd, Asad ibn al-Furat, Ahmad ibn Maniʿ, ʿAli ibn Muslim al-Tusi, ʿAmr ibn Abi ʿAmr al-Harrani, ʿAmr al-Naqid, and many others.

His father was poor and kept a small, struggling shop, so Abu Hanifa regularly supplied Abu Yusuf with money—one hundred dirhams after another.

ʿAli ibn Harmalah al-Taymi related from Abu Yusuf: “I was seeking knowledge while in straightened circumstances. My father came and said, ‘My son, do not stretch out your legs in Abu Hanifa’s gathering; you are in need.’ I preferred obedience to my father, whereupon Abu Hanifa gave me one hundred dirhams and said, ‘Stay in the study circle; when this is spent, let me know.’ A few days later he gave me another hundred.”

It is also said that he was reared an orphan and that his mother placed him in the care of a cloth-finisher.

Muhammad ibn al-Hasan said: “Abu Yusuf once fell ill, so Abu Hanifa visited him. When he left the house he remarked, ‘If this young man were to die, he would be the most learned person alive.’”

Ahmad ibn Hanbal said: “The first time I ever wrote down hadith, I used to attend the sessions of Abu Yusuf.”