ʿAlī al-Thaqafī’s firmness of intellect?”
He replied, “That is the very intellect of the Companions and their Followers among the people of Madinah.”
Someone asked, “How so?”
He said, “Mālik was one of the most clear-sighted men of his age, and it was said that he inherited the acumen of the Followers with whom he had sat. Then Yahyā ibn Yahyā al-Nīsābūrī kept his company and took from his intelligence and demeanor. After that, Muḥammad ibn Naṣr sat with Yahyā ibn Yahyā for many years until he absorbed his bearing and understanding; after Yahyā no jurist in Khurāsān was deemed more intelligent than Ibn Naṣr. Later Abū ʿAlī al-Thaqafī accompanied him for four years, and after him no one was considered shrewder than Abū ʿAlī.”
ʿAbd Allāh ibn Muḥammad al-Isfarāyinī said, “I heard Muḥammad ibn ʿAbd Allāh ibn ʿAbd al-Ḥakam say, ‘Muḥammad ibn Naṣr was an imam in Egypt—so what must he have been in Khurāsān!’ ”
Judge Muḥammad ibn Muḥammad said, “The earliest of our shaykhs used to say: ‘The men of Khurāsān are four: Ibn al-Mubārak, Ibn Rāhwayh, Yahyā ibn Yahyā, and Muḥammad ibn Naṣr.’ ”
Among Muḥammad ibn Naṣr’s own words: “Since some sins amount to disbelief and others do not, the Exalted differentiated between them, making them three kinds: one kind is disbelief, one is defiant sin (fusuq), and one is disobedience that is neither disbelief nor defiant sin. Yet He informed us that He has made all of them hateful to the believers.
“Because every act of obedience falls under faith and none lies outside it, He did not distinguish among them. He did not say, ‘He has endeared to you faith, the obligatory duties, and the rest of the acts of obedience’; rather, He expressed it succinctly: ‘He has endeared faith to you’ (Qur’an 49:7), and that phrase encompasses all acts of obedience. Thus He has made the prayer, the zakat, and every other form of devotion beloved to them as a matter of religious love, and they abhor sins out of religious aversion. This is borne out by the Prophet’s saying, ‘Whoever is pleased by his good deed and distressed by his bad deed, he is a believer.’ (1)"