When the Prophet ﷺ would come out from relieving himself, he would say, "Your forgiveness."
إن النبي ﷺ لو كان إذا خرج من الغائط قال: غفرانك.
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Abu Dawud (30), Tirmidhi (7), and Ibn Majah (300) all narrated it through Israil bin Yunus, from Yusuf bin Abu Burda, from his father, from Ayesha. Tirmidhi said, "Hasan gharib, we do not know it except through the hadith of Israil from Yusuf bin Abu Burda." He also said, "We do not know in this chapter except the hadith of Ayesha from the Prophet ﷺ."Its isnad is hasan because of Yusuf bin Abu Burda, who is not that well known, and no criticism of him has been recorded, while Ajli and Ibn Hibban both deemed him trustworthy. Nawawi graded his hadith sahih in Adhkar, as did Ibn Hajar in Nataij Afkar (1/214). Dhahabi also deemed him trustworthy in Kashif, so at the very least he does not fall below the rank of "saduq," even though Ibn Hajar said in Taqrib, "maqbul." Ibn Khuzayma (90), Ibn Hibban (1444), and Hakim (1/158) also graded it sahih, all through this same route.Hakim said, "This is a sahih hadith, for Yusuf bin Abu Burda is among the trustworthy members of the family of Abu Musa, and we have not found anyone who criticizes him, and he mentioned that his father heard from Ayesha ... As for Tirmidhi's statement that it is gharib, that is because Israil narrated it alone, and Israil is trustworthy."His saying "Ghufranaka" means, "I ask You for Your forgiveness." Khattabi said, "There are two opinions regarding the interpretation of this, and regarding his following up leaving the toilet with this supplication. One is that he sought forgiveness for having left off remembering Allah Almighty during the time he spent in the toilet, for ﷺ would not abandon the remembrance of Allah except when necessary. So it is as though he saw abandoning remembrance in that state as a shortcoming, and counted it against himself as a sin, and so he made up for it by seeking forgiveness. It is also said that its meaning is repentance for his shortcoming in giving thanks for the blessing that Allah Almighty had bestowed upon him, for He fed him, then digested it for him, then made it easy for the waste to leave his body, so he saw his gratitude as falling short of what these blessings deserved, and so he resorted to seeking forgiveness for that." End of quote.Nothing has been established in this chapter except the hadith of Ayesha. Abu Hatim Razi said, "The most sahih thing in this chapter is the hadith of Ayesha."I say, it is as he said. As for the hadith of Malik bin Anas from the Prophet ﷺ that when he left the toilet he said, "Praise be to Allah who removed the discomfort from me and gave me health," it was narrated by Ibn Majah (301) through Ismail bin Muslim, from Hasan and Qatada, from Anas. Busiri said in Zawaid, "Ismail bin Muslim is unanimously judged daif, and the hadith with this wording is not established." End of quote.I say, Ismail bin Muslim is Makki, Abu Ishaq, who was originally from Basra, then settled in Makkah. Ibn Main said, "He is nothing." Abu Hatim and Abu Zura said, "His hadith is daif." Nasai said, "He is discarded."Also in this chapter is the hadith of Abu Dharr, recorded by Ibn Sunni (21), which contains someone unknown. And the hadith of Abdullah bin Umar. Munziri said in Mukhtasar Sunan Abu Dawud, "The chains of these hadiths are daif, and this is why Abu Hatim Razi said, 'The most sahih thing in it is the hadith of Ayesha.'" End of quote.