and liquid. Ahmad would sometimes rely on hadiths that later proved to him to be defective, as when he relied on the saying:

“A vow involving disobedience is not valid, and its expiation is the same as for an oath.”

Later, when its defect became clear to him, he relied on other evidence. Al-Bukhārī, al-Tirmidhī and others, however, identified the defect in Ma‘mar’s hadith and explained his error. Their judgment is correct.

Here al-Bukhārī cited Ibn ‘Uyaynah as saying: “I heard it from al-Zuhrī repeatedly; he narrated it only from ‘Ubayd Allāh ibn ‘Abd Allāh.” Its wording contains only the instruction:

“Discard it and what surrounds it, and eat the rest.”

Mālik and others narrated it likewise. Al-Bukhārī also cited Yūnus’s report that al-Zuhrī was asked about an animal dying in clarified butter, whether solid or otherwise. He gave his ruling by citing the report:

“The Prophet, may Allah bless him and grant him peace, gave instructions concerning a mouse that had died in clarified butter, ordering that what was close to it be discarded.”

This, then, was al-Zuhrī’s ruling concerning both solid and liquid clarified butter. How could he have narrated a distinction between them in this hadith when he cites that very hadith as evidence that both types have the same ruling, narrating it by meaning? Al-Zuhrī had the strongest memory of anyone in his time, so much so that it is said that no error or lapse of memory in any hadith is known of him, even though no one in his time possessed more hadiths than he did.

It is also said that he preserved for the Muslim community ninety teachings of the Sunnah which no one else transmitted. Sulaymān ibn ‘Abd al-Malik wrote down a book from his recitation from memory, then asked him to repeat it a year later, and he did not miss a single letter. Thus, even if the only question concerning this hadith were whether al-Zuhrī or Ma‘mar had forgotten, attributing the lapse to Ma‘mar would be more appropriate, by the unanimous agreement of the scholars