Al-Kāfi - Volume 3 > Recitations in Salah (prayer)
Hadith #15

15ـ عَنْهُ عَنْ مُحَمَّدِ بْنِ الْحُسَيْنِ عَنِ ابْنِ مَحْبُوبٍ عَنِ ابْنِ رِئَابٍ عَنِ الْحَلَبِيِّ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ الْسَّلام) قَالَ سَأَلْتُهُ هَلْ يَقْرَأُ الرَّجُلُ فِي صَلاَتِهِ وَثَوْبُهُ عَلَى فِيهِ قَالَ لاَ بَأْسَ بِذَلِكَ إِذَا أَسْمَعَ أُذُنَيْهِ الْهَمْهَمَةَ.

15. It is a narration from him (narrator of previous Hadith) by Muhammad ibn al-Husayn from ibn Mahbub from ibn Ri’ab from al- Halabiy who has said the following: “I once asked abu ‘Abd Allah, ‘Alayhi al-Salam, ’Can one recite in Salah (prayer) with his clothes on his mouth? He (the Imam) said, ‘It is not harmful if his ears can hear his humming.’”