Sahih Muslim Book - 2, Hadith - 539

و حَدَّثَنِي زُهَيْرُ بْنُ حَرْبٍ حَدَّثَنَا يَعْقُوبُ بْنُ إِبْرَاهِيمَ حَدَّثَنَا أَبِي عَنْ ابْنِ شِهَابٍ عَنْ عَطَاءِ بْنِ يَزِيدَ اللَّيْثِيِّ عَنْ حُمْرَانَ مَوْلَى عُثْمَانَ أَنَّهُ رَأَى عُثْمَانَ دَعَا بِإِنَاءٍ فَأَفْرَغَ عَلَى كَفَّيْهِ ثَلَاثَ مِرَارٍ فَغَسَلَهُمَا ثُمَّ أَدْخَلَ يَمِينَهُ فِي الْإِنَاءِ فَمَضْمَضَ وَاسْتَنْثَرَ ثُمَّ غَسَلَ وَجْهَهُ ثَلَاثَ مَرَّاتٍ وَيَدَيْهِ إِلَى الْمِرْفَقَيْنِ ثَلَاثَ مَرَّاتٍ ثُمَّ مَسَحَ بِرَأْسِهِ ثُمَّ غَسَلَ رِجْلَيْهِ ثَلَاثَ مَرَّاتٍ ثُمَّ قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مَنْ تَوَضَّأَ نَحْوَ وُضُوئِي هَذَا ثُمَّ صَلَّى رَكْعَتَيْنِ لَا يُحَدِّثُ فِيهِمَا نَفْسَهُ غُفِرَ لَهُ مَا تَقَدَّمَ مِنْ ذَنْبِهِ.

It was narrated from Humran, the freed slave of 'Uthman, that he saw 'Uthman call for a vessel (of water). He poured some (water) onto his hands three times and washed them, then he put his right hand into the vessel (took out water) and rinsed his mouth and nose. Then he washed his face three times and his hands up to the elbows three times. Then he wiped his head, then he washed his feet three times. Then he said: "The Messenger of Allah (s.a.w) said: 'Whoever performs Wudu' as I have just done it, then prays two Rak'ah in which he does not let his mind wander, will be forgiven his previous sins."'