Sayyiduna Anas bin Malik (may Allah be pleased with him) narrates that when the Messenger of Allah (peace and blessings be upon him) would go out to relieve himself, I would bring water to him, and he (peace and blessings be upon him) would perform istinja with it and wash his back.

It is narrated from Sayyiduna Anas bin Malik (may Allah be pleased with him) that when the Prophet Muhammad (peace and blessings be upon him) would go to relieve himself, I would go with him carrying a stick and a water vessel. When he (peace be upon him) would come out (after relieving himself), he would perform istinja (cleaning) with water and make ablution from the water vessel.

Sayyiduna Abu Mu'adh (may Allah be pleased with him) narrates that I heard Sayyiduna Anas (may Allah be pleased with him) saying that when the Messenger of Allah (peace and blessings be upon him) would go to relieve himself, I and another boy would follow him carrying a water vessel. Imam Abu Bakr (may Allah have mercy on him) says that this Abu Mu'adh is 'Ata bin Abi Maymunah.

Sayyiduna Anas bin Malik (may Allah be pleased with him) narrates that when the Messenger of Allah (peace and blessings be upon him) would enter the toilet, I and another boy like me would carry a water vessel and take it to him. The Prophet (peace and blessings be upon him) would perform istinja (cleaning) with water.