Narrated Anas b. Malik :

The Messenger of Allaah ( sal Allaahu alayhi wa sallam ) entered a park. He was accompanied by a boy who had a jug of water with him. He was the youngest of us. He placed it near the lote-tree. He ( the Prophet, sal Allaahu alayhi wa sallam ) relieved himself. He came to us after he had cleansed himself with water.

حَدَّثَنَا وَهْبُ بْنُ بَقِيَّةَ، عَنْ خَالِدٍ، - يَعْنِي الْوَاسِطِيَّ - عَنْ خَالِدٍ، - يَعْنِي الْحَذَّاءَ - عَنْ عَطَاءِ بْنِ أَبِي مَيْمُونَةَ، عَنْ أَنَسِ بْنِ مَالِكٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم دَخَلَ حَائِطًا وَمَعَهُ غُلاَمٌ مَعَهُ مِيضَأَةٌ وَهُوَ أَصْغَرُنَا فَوَضَعَهَا عِنْدَ السِّدْرَةِ فَقَضَى حَاجَتَهُ فَخَرَجَ عَلَيْنَا وَقَدِ اسْتَنْجَى بِالْمَاءِ ‏.‏