Muwatta Malik 459
موطأ مالك#459SahihYahya related to me from Malik from Hisham ibn Urwa from his father from A'isha, the wife of the Prophet, mayAllah bless him and grant him peace, that the Prophet, may Allah bless him and grant him peace, saw spittle, or mucus or phlegm, on the wall of the qibla and scraped it off
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Salim al-HilaliSahih
In-book reference: 14:5