He prayed Subh and recited Ar-Rum, but he stumbled in his recitation. When he had finished praying he said: 'What is the matter with people who pray with us without purifying themselves properly? Those people make us stumble in reciting Quran.'" (Using translation from Nasāʾī 947)  

عَنْ رَجُلٍ مِنْ أَصْحَابِ النَّبِيِّ ﷺ عَنِ النَّبِيِّ ﷺ أَنَّهُ صَلَّى صَلَاةَ الصُّبْحِ فَقَرَأَ الرُّومَ وَالْتُبِسَ عَلَيْهِ فَلَمَّا صَلَّى قَالَ «مَا بَالُ أَقْوَامٍ يُصَلُّونَ مَعَنَا لَا يُحْسِنُونَ الطُّهُورَ فَإِنَّمَا يَلْبِسُ عَلَيْنَا الْقُرْآنَ أُولَئِكَ»