Sahih al-Bukhari 159
Narrated Humran:
(the slave of 'Uthman) I saw 'Uthman bin 'Affan asking for a tumbler 
     of water (and when it was brought) he poured water over his hands and 
     washed them thrice and then put his right hand in the water container 
     and rinsed his mouth, washed his nose by putting water in it and then 
     blowing it out. then he washed his face and forearms up to the 
     elbows thrice, passed his wet hands over his head and washed his feet 
     up to the ankles thrice. Then he said, "Allah's Messenger (ﷺ) said 'If 
     anyone performs ablution like that of mine and offers a two-rak'at 
     prayer during which he does not think of anything else (not related to
     the present prayer) then his past sins will be forgiven.' "
حَدَّثَنَا عَبْدُ الْعَزِيزِ بْنُ عَبْدِ اللَّهِ الأُوَيْسِيُّ، قَالَ حَدَّثَنِي إِبْرَاهِيمُ بْنُ سَعْدٍ، عَنِ ابْنِ شِهَابٍ، أَنَّ عَطَاءَ بْنَ يَزِيدَ، أَخْبَرَهُ أَنَّ حُمْرَانَ مَوْلَى عُثْمَانَ أَخْبَرَهُ أَنَّهُ، رَأَى عُثْمَانَ بْنَ عَفَّانَ دَعَا بِإِنَاءٍ، فَأَفْرَغَ عَلَى كَفَّيْهِ ثَلاَثَ مِرَارٍ فَغَسَلَهُمَا، ثُمَّ أَدْخَلَ يَمِينَهُ فِي الإِنَاءِ فَمَضْمَضَ، وَاسْتَنْشَقَ، ثُمَّ غَسَلَ وَجْهَهُ ثَلاَثًا، وَيَدَيْهِ إِلَى الْمِرْفَقَيْنِ ثَلاَثَ مِرَارٍ، ثُمَّ مَسَحَ بِرَأْسِهِ، ثُمَّ غَسَلَ رِجْلَيْهِ ثَلاَثَ مِرَارٍ إِلَى الْكَعْبَيْنِ، ثُمَّ قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏
"‏ مَنْ تَوَضَّأَ نَحْوَ وُضُوئِي هَذَا، ثُمَّ صَلَّى رَكْعَتَيْنِ، لاَ يُحَدِّثُ فِيهِمَا نَفْسَهُ، غُفِرَ لَهُ مَا تَقَدَّمَ مِنْ ذَنْبِهِ ‏"‏‏.‏