He then set out on his travels around the year 210 AH and performed the pilgrimage.
During that journey he studied under: ʿAbd al-Malik ibn al-Mājishūn, Mutarrif ibn ʿAbd Allāh al-Yasārī, Asad ibn Mūsā—nicknamed “al-Sunnah,” Aṣbagh ibn al-Faraj, Abū Ṣāliḥ, Ibrāhīm ibn al-Mundhir al-Ḥizāmī, and a number of the students of Mālik and al-Layth. He returned to Córdoba laden with copious knowledge and a wide mastery of jurisprudence.
He was praised for his acumen in fiqh, held in high regard, widely famous, and the author of many works. Yet, in the field of transmission he was not meticulous; he would take up hadith rather hastily, passing it on simply because he had found it in a manuscript (1) or had received a bare ijāza (2), without subjecting it to the rigorous scrutiny practiced by the hadith specialists.
Among his writings are: the multi-volume work al-Wāḍiḥa, al-Jāmiʿ (3), The Merits of the Companions, Singular Terms in Hadith, A Commentary on the Muwaṭṭaʾ, a book on The Wars of Islam, The Virtue of the Two Mosques, The Conduct of the Imām toward Those Who Deviate, and Ṭabaqāt
(1) Al-wijada: this occurs when someone comes across hadiths written in the handwriting of their transmitter—whether he met or heard from him or not—or when he finds hadiths in books by well-known authors. In all such cases he may not relate them directly from their original transmitters; rather he should say, “I found this in the handwriting of so-and-so,” if he can recognise and trust the script, or state, “So-and-so said…,” and the like. The leading scholars hold that one may act upon such material once he is confident that the report is indeed in the shaykh’s own hand, or that the book being quoted is reliably attributed to its trustworthy author, and that the isnad is sound.
(2) Al-ijaza: an authorisation whereby a shaykh permits another person to transmit his narrations or writings, in effect informing him of what he may report on his authority. Scholars have differed on the admissibility of narrating and acting upon an ijaza; the majority stipulate that the grantor must be knowledgeable about what he authorises, recognised for that expertise, trustworthy in religion and transmission, and that the recipient be a qualified student of knowledge, so that learning is not placed where it does not belong. For details see: al-Baa‘ith al-Hathith, pp. 119–122; the introduction to Jami‘ al-Usul, 1/81, 83.
(3) Titled al-Jawami‘ in Tarikh ‘Ulama’ al-Andalus, 1/270, and in Tartib al-Madarik, 3/35. A more extensive list of his sources is given in Tartib al-Madarik, 3/35–36.