To wash the private parts with water after answering the call of nature

Narrated Anas bin Malik:

Whenever Allah's Apostle went to answer the call of nature, I along with another boy used to accompany him with a tumbler full of water. (Hisham commented, "So that he might wash his private parts with it.)"

حَدَّثَنَا أَبُو الْوَلِيدِ، هِشَامُ بْنُ عَبْدِ الْمَلِكِ قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ أَبِي مُعَاذٍ ـ وَاسْمُهُ عَطَاءُ بْنُ أَبِي مَيْمُونَةَ ـ قَالَ سَمِعْتُ أَنَسَ بْنَ مَالِكٍ، يَقُولُ كَانَ النَّبِيُّ ﷺ إِذَا خَرَجَ لِحَاجَتِهِ أَجِيءُ أَنَا وَغُلاَمٌ مَعَنَا إِدَاوَةٌ مِنْ مَاءٍ. يَعْنِي يَسْتَنْجِي بِهِ.