Sunan an-Nasa'i 145
سنن النسائي#145Sahihأَخْبَرَنَا مُحَمَّدُ بْنُ عَبْدِ الأَعْلَى، قَالَ حَدَّثَنَا خَالِدٌ، عَنْ شُعْبَةَ، عَنْ جَامِعِ بْنِ شَدَّادٍ، قَالَ سَمِعْتُ حُمْرَانَ بْنَ أَبَانَ، أَخْبَرَ أَبَا بُرْدَةَ، فِي الْمَسْجِدِ أَنَّهُ سَمِعَ عُثْمَانَ، يُحَدِّثُ عَنْ رَسُولِ اللَّهِ صلى الله عليه وسلم يَقُولُ " مَنْ أَتَمَّ الْوُضُوءَ كَمَا أَمَرَهُ اللَّهُ عَزَّ وَجَلَّ فَالصَّلَوَاتُ الْخَمْسُ كَفَّارَاتٌ لِمَا بَيْنَهُنَّ " .
It was narrated that Jami' bin Shaddad said:"I heard Humran bin Aban tell Abu Burdah in the Masjid that he heard 'Uthman narrating that the Messenger of Allah (ﷺ) said: 'Whoever performs Wudu' completely as commanded by Allah, the five daily prayers will be an expiation for whatever comes in between them
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 1:146