عن عائشة قالت : كان النبي صلى الله عليه وسلم إذا خرج من الغائط قال: "غُفْرَانَكَ".
وعن ابن مسعود قال:«أتى النبي صلى الله عليه وسلم الغائط فأمرني أن آتيه بثلاثة أحجار، فوجدت حجرين، والتمست الثالث فلم أجده، فأخذت رَوْثَةً فأتيته بها، فأخذ الحجرين وألقى الروثة». وقال:«هذا رِكْسٌ». [حديث عائشة صحيح.
وحديث ابن مسعود صحيح] - [حديث عائشة: رواه أبو داود والترمذي وابن ماجه والدارمي وأحمد.
وحديث ابن مسعود: رواه البخاري] المزيــد ...
‘Ā’ishah reported that when the Prophet (may Allah's peace and blessings be upon him) exited the privy, he would say:"O Allah, grant me Your forgiveness!"
Ibn Mas‘ūd reported that the Prophet (may Allah's peace and blessings be upon him) went to the toilet one day and ordered me to bring him three stones. I found two stones and searched for the third but could not find it. So I took a dried piece of dung and brought it to him. He took the two stones and threw away the dung and said:"This is a filth." Sahih/Authentic. - [Ibn Maajah]
In the Hadīth reported by ‘A'ishah (may Allah be pleased with her) the Prophet (may Allah's peace and blessings be upon him) used to say "O Allah, I ask Your forgiveness" upon exiting from the place where he was answering the call of nature. Perhaps the wisdom behind this - Allah knows best - is that it sounds appropriate to ask Allah to relieve him spiritually after he relieved himself physically.
The Hadīth reported by Ibn Mas‘ūd (may Allah be pleased with him) states that when the Prophet (may Allah's peace and blessings be upon him) went to answer the call of nature, he ordered Ibn Mas‘ūd to bring him three stones, but he found two stones only. So he took a dried animal dung and brought it to the Prophet, thinking that it is permissible to use it for cleaning. The Prophet (may Allah's peace and blessings be upon him) took the two stones and cleansed himself with them, and threw the dung. Then he clarified the reason as to why he threw it; that it is impure and is not correct to cleanse oneself with it. This ruling applies to every type of dung. Because if it is coming from an animal whose meat is not edible, as mentioned in the Hadīth, then it is filthy and impure; if it is coming from an animal whose meat is edible, then it serves as food for animals of the Jinn.