The condition of the two Shaykhs (al-Bukhari and Muslim)

"The condition of the two Shaykhs" (shart al-shaykhayn) means what al-Bukhari and Muslim held themselves to in choosing the hadiths of their Sahihs. ² In the introduction to Irshad al-Sari, summarising the introduction to Fath al-Bari, al-Qastallani relays Ibn Tahir al-Maqdisi's point that neither is reported to have said "my condition is to include such-and-such"; their conditions are known only from studying their books. ²

Al-Qastallani notes that the community agreed in accepting the two Sahihs and differed over which is stronger, the majority explicitly preferring al-Bukhari's. ³

• He reads Abu 'Ali al-Naysaburi's saying "there is nothing under the sky sounder than Muslim's book" as denying that any book is sounder than Muslim's, not as asserting that it is sounder than al-Bukhari's. ³
• He takes the preference of some Maghribis for Muslim's Sahih to concern its fine presentation and arrangement, not its soundness. ³
• He gives reasons for preferring al-Bukhari: in connection, because al-Bukhari requires proof that a narrator met his source at least once while Muslim is content with contemporaneity; in uprightness and precision, because more of Muslim's narrators were criticised; and in freedom from anomaly and defect, because fewer of al-Bukhari's hadiths were criticised than Muslim's. ³ See connection of the chain.

Al-Qastallani relays that a Sahih author's inclusion of a narrator implies his uprightness and precision in that author's view — all the more so since the community agreed to call the two books "the Sahihs" — at least for the main reports, while narrators of corroborating and suspended reports vary in standing; and that criticism is accepted only when its damaging ground is explained. ⁴ Abu al-Hasan al-Maqdisi used to say of a narrator used in the Sahih, "he has crossed the bridge" — what was said about him is no longer considered. ⁵

Not yet covered here: an academic view of the two Sahihs' conditions.

Al-Nawawi quotes Ibn al-Salah that Muslim's condition in his Sahih is a chain connected by reliable men from reliable men from beginning to end, free of anomaly and defect — which is the definition of sound hadith. ⁶ He explains the formula "sound on Muslim's condition but not al-Bukhari's" as meaning that some narrators met the conditions for Muslim but not for al-Bukhari — such as Abu al-Zubayr al-Makki, Suhayl b. Abi Salih, al-'Ala' b. 'Abd al-Rahman and Hammad b. Salama — and conversely for men al-Bukhari relied on but Muslim did not, such as 'Ikrima, client of Ibn 'Abbas. ⁶ Al-Nawawi counts among the reasons for preferring al-Bukhari's book that Muslim treats an "'an" chain as connected on mere contemporaneity, whereas al-Bukhari does not until the two are proven to have met. ⁷

In the [[work/al-mustadrak-ala-al-sahihayn|Mustadrak]], al-Hakim would explain the two masters' omission of a hadith by its Companion having only one transmitter, as when he says they refrained from the hadith of 'Urwa ibn Mudarris because only al-Sha'bi transmitted from him. ⁸ Muqbil al-Wadi'i answers this with the list that al-Daraqutni drew up in [[work/al-ilzamat-ala-sahih-al-bukhari|al-Ilzamat]] of Companions whom both masters or one of them included although each had only one transmitter: Mirdas al-Aslami and 'Adi ibn 'Amira through Qays ibn Abi Hazim, 'Itban ibn Malik through Mahmud ibn al-Rabi', al-Musayyab ibn Hazn through his son Sa'id, and others. ⁹

Al-Hakim relates that al-Daraqutni asked him why the two masters left out the hadith of Usama ibn Sharik (may God be pleased with him); he answered that they found no transmitter from Usama other than Ziyad ibn 'Ilaqa, and al-Daraqutni replied with Companions they included who had a single transmitter. Al-Wadi'i reads this as al-Hakim conceding. ¹⁰ Elsewhere in the Mustadrak al-Hakim even states the opposite of his own view, arguing that the two masters included a number of Companions who each had only one transmitter. ¹¹