Umm Muiminin reported that the Messenger of Allah ﷺ saw some mucus, or spittle, or phlegm on the wall of the qiblah, so he scraped it off.
أم المؤمنين أن رسول الله ﷺ رأى في جدار القبلة مخاطا- أو بصاقا-، أو نخامة فحكه.
Malik narrated it in the Book of the qibla (5) from Hisham bin Urwa, from his father, from Ayesha, as related above.Bukhari narrated it in the Book of Prayer (407) from Abdullah bin Yusuf, and Muslim narrated it in the Book of Mosques (549) from Qutayba bin Saeed, both of them from Malik, with the same wording.