Uthman ibn Affan reported: The Messenger of Allah, peace and blessings be upon him, said, “Whoever perfects his ablution as Allah Almighty has commanded him, the prescribed prayers will be an expiation for what occurs between them.”
Source: Ṣaḥīḥ Muslim 231
Grade: Sahih (authentic) according to Muslim
عَنْ عُثْمَانَ بْنِ عَفَّانَ قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مَنْ أَتَمَّ الْوُضُوءَ كَمَا أَمَرَهُ اللَّهُ تَعَالَى فَالصَّلَوَاتُ الْمَكْتُوبَاتُ كَفَّارَاتٌ لِمَا بَيْنَهُنَّ
231 صحيح مسلم كتاب الطهارة باب فضل الوضوء والصلاة عقبه