Hishām, Isḥāq al-Azraq, Wahb ibn Jarīr, ʿAbd al-Raḥmān ibn Mahdī, and others of their generation.
Among those who narrated from him are al-Bukhārī, Muslim, al-Nasāʾī, Abū Zurʿah, Ibrāhīm ibn Abī Ṭālib, Jaʿfar al-Firyābī, al-Ḥusayn al-Qabbānī, Ibn Khuzaymah, Abū al-ʿAbbās al-Sarrāj, and many more.
Al-Bukhārī records in his book Actions of the Servants a transmission from ʿUbayd Allāh ibn Saʿīd on the authority of Ḥammād ibn Zayd; this seems unlikely, for I do not believe he ever met him.
Al-Nasāʾī said, “Reliable, trustworthy; hardly anyone we have written from is his equal.”
Ibrāhīm ibn Abī Ṭālib remarked, “No one who came to us in Nīshāpūr was more accurate or more proficient than Abū Qudāmah.”
Ibn Ḥibbān al-Bustī stated, “He is the one who made the Sunnah manifest in Sarakhs and invited the people to it.”
Yahyā ibn Muḥammad al-Dhuhlī said, “He was an imam, virtuous and good.”
Al-Bukhārī ⦗1⦘ said that he died in 241 AH, while others held that he passed away in Farabr.
A high-level isnād of his concerning the traits of the hypocrite has reached me, and I have cited it in Tadhkirat al-Ḥuffāẓ.