Sulaymān ibn al-Khalīl said: “I heard al-Harbī remark, ‘In Abū ʿUbayd’s Gharīb al-Ḥadīth there are fifty-three reports that lack any authentic basis (1).’
Abū al-Ḥasan al-Darqutnī said: “Al-Harbī was an imam, an author, learned in every field, outstanding in every branch of knowledge, and altogether trustworthy.”
Abū Bakr al-Shāfiʿī related: “I heard Ibrāhīm al-Harbī say, ‘I possess from ʿAlī ibn al-Madīnī a qimaṭr (large leather chest) full of material, yet I do not relate anything from him, because I once saw him at the time of Maghrib, sandals in hand, hurrying off. I asked, “Where are you going?” He replied, “To catch the prayer with Abū ʿAbd Allāh.” I assumed he meant Aḥmad ibn Ḥanbal, so I asked, “Who is Abū ʿAbd Allāh?” He answered, “Ibn Abī Duʿad (2).”’
It is also said that when the caliph al-Muʿtaḍid sent ten thousand dirhams to al-Harbī, he returned them. People urged him, “Then at least distribute them,” but he refused. Later, when he fell ill, al-Muʿtaḍid dispatched one thousand dinars, yet he still would not accept them. His daughter protested, whereupon he said, “Are you afraid that you will be poor after I die?” She replied, “Yes.” He said, “In that corner there are twelve thousand separate booklets—on ḥadīth, language, and other subjects—that I have written …”
(1) Bibliographic reference: Al-Khatib al-Baghdadi, Tarikh Baghdad, vol. 6, pp. 35-36; the supplementary passage is taken from the same source, and the continuation of the report is also there: “I have marked it in the book of al-Sarawi.”
Commentary: Hence a student of sacred learning may not rely on the prophetic reports casually scattered in the lexicographical works on rare expressions without first identifying who transmitted them and carefully inspecting their chains of narration.
(2) Bibliographic reference: See the account in Tarikh Baghdad, vol. 6, p. 37, and in al-Dhahabi, Mizan al-I‘tidal, vol. 3, p. 138.
Commentary: To treat his connection with Ibn Abi Dawad or his acceptance of a monetary award from him as a defect in his reliability is an instance of extreme rashness that merits censure and rebuke. The claim that he considered Qays ibn Abi Hazim weak is dismissed by al-Khatib in his Tarikh. The author, al-Dhahabi, states in his Mizan (3/141) while refuting al-‘Uqayli: “Not everyone who holds a heterodox view, commits a lapse, or has sins is thereby discredited so that his hadith becomes weak; being free from every error or fault is not a prerequisite for trustworthiness. Rather, by listing many trustworthy transmitters who possessed minor innovations or slight mistakes despite their vast learning, we intend to show that others may still outweigh them in reliability when they are compared or disagreed with.”
As for Ali ibn al-Madini, he reached the summit in knowledge of the subtle defects (‘ilal) of prophetic hadith, combined with consummate expertise in evaluating transmitters, prodigious memorization, and deep mastery of the discipline; indeed, he was very likely unrivalled in his time.