She said, "I used to scrape the semen off the garment of the Messenger of Allah ﷺ."
قالت: كنت أفرك المني من ثوب رسول الله ﷺ.
Muslim narrated it in the Book of Purification (288:106) from Umar bin Hafs bin Ghiyath, who said, my father narrated to us, from Amash, from Ibrahim, from Aswad and Hammam, from Ayesha, and he related it as mentioned. Muslim mentioned many routes for Ayesha's hadith about rubbing off semen, but Bukhari confined himself to mentioning the hadith about washing off semen and did not mention the hadith about rubbing it off, even though he titled the chapter, "Chapter on washing off semen and rubbing it off." Perhaps by this chapter title he intended to establish the purity of semen, according to the view of Shafii, Ahmad, and the scholars of hadith, since washing it off and rubbing it off are equivalent.