Those who transmitted hadith from him include al-Bukhārī, Abū Dāwūd, al-Tirmidhī, Abū Bakr ibn Abī ʿĀṣim, Jaʿfar al-Firyābī, Abū Yaʿlā al-Mawṣilī, al-Ḥasan ibn Sufyān, Muḥammad ibn ʿUmar ibn Bujayr, Yaḥyā ibn Ṣāʿid, the judge Abū ʿAbd Allāh al-Maḥāmilī, and a great many others.

Abū Ḥātim said, “He is truthful (ṣadūq); in Baghdad he enjoyed an extraordinary dignity, and Aḥmad ibn Ḥanbal held him in high regard and venerated him.”⦗1⦘

ʿAbd Allāh ibn Aḥmad reported from his father: “Not a single day passed over Ibn al-Bazzār without his engaging in some act of goodness. We used to attend a certain shaykh, and while we would sit reviewing our lessons until the shaykh emerged, Ibn al-Bazzār would remain standing in prayer.”⦗2⦘

Abū al-ʿAbbās al-Sarrāj said: I heard al-Ḥasan ibn al-Ṣabbāḥ relate:

“I was brought before the caliph al-Maʾmūn three times. The first time, he had been informed that I was enjoining the good—he had prohibited anyone from doing so—so I was seized and taken in to him. He asked me, ‘Are you al-Ḥasan al-Bazzār?’

‘I am, Commander of the Faithful,’ I replied.

‘And you enjoin the good?’ he said.

‘No; rather, I forbid the wrong,’ I answered.

He thereupon had me hoisted onto a man’s back, struck me five lashes, and then set me free.

“I was brought in a second time after it was reported that I reviled ʿAlī (may Allah ennoble his countenance). When I entered, he said, ‘You curse ʿAlī?’

I replied, ‘May Allah bless my master and liege-lord ʿAlī, O Commander of the Faithful! I do not even curse Yazīd—he is your cousin—so how could I ever curse my master and liege-lord?’

He said, ‘Release him.’

“On yet another occasion I travelled to Byzantine territory, to al-Badhandūn, during the miḥna (inquisition), and I was handed over to …”