relied solely on Ibn Ḥibbān’s endorsement, and that alone is no authority.

What further demonstrates the weakness of Ibn Rifāʿah is that Mālik, Jarīr, and al-Darāwardī—as cited by Muslim 7/11—and Maʿmar—as cited by Aḥmad 2/268—all narrate the same report from Suhayl, yet none of them state that the Prophet ﷺ fasted on Mondays and Thursdays or that he was questioned about it. The narration is likewise transmitted by Muslim ibn Abī Maryam from Abū Ṣāliḥ; Muslim also records it, and it is cited in al-Irwāʾ 4/105.

I judged the ḥadith authentic only because its second half is sound, as you can see, while its first half is supported by corroborating reports—among them the narration of Usāmah ibn Zayd, which adds:

“These two days are when deeds are presented to the Lord of all worlds, and I love for my deeds to be presented while I am fasting.”

Al-Nasāʾī and Aḥmad relate this wording with a good chain; Abū Dāwūd transmits it via a second route, and Ibn Khuzaymah via a third—see al-Targhīb. The author, however, merged al-Nasāʾī’s route with that of Abū Dāwūd into one chain; this is one of his slips, so take note.

Under the heading “Fasting Three Days of Every Month” he writes: “It is reported that the Messenger of Allah ﷺ used to fast—in one month—on Saturday, Sunday, and Monday, and—in the next month—on Tuesday, Wednesday, and Thursday.”

I say: To assert categorically that this stems from the Prophet ﷺ is open to question, for it comes through Sufyān → Manṣūr → Khaythamah → ʿĀʾishah, who said … It was recorded by al-Tirmidhī, who commented: “A ḥasan (sound) ḥadith, but ʿAbd al-Raḥmān ibn Mahdī narrated it from Sufyān without tracing it back to the Prophet.”