Al-Kāfi

Hadith 1537
dress-adornmentprayer-etiquette
6ـ مُحَمَّدُ بْنُ يَحْيَى عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنْ عَلِيِّ بْنِ حَدِيدٍ عَنْ جَمِيلٍ قَالَ سَأَلَ مُرَازِمٌ أَبَا عَبْدِ الله (عَلَيْهِ الْسَّلام) وَأَنَا مَعَهُ حَاضِرٌ عَنِ الرَّجُلِ الْحَاضِرِ يُصَلِّي فِي إِزَارٍ مُرْتَدِياً بِهِ قَالَ يَجْعَلُ عَلَى رَقَبَتِهِ مِنْدِيلاً أَوْ عِمَامَةً يَتَرَدَّى بِهِ.
6. Muhammad ibn Yahya has narrated from Ali ibn Hadid from Jamil who has said the following: “Murazim once asked abu ‘Abd Allah (a.s.), when I was present, about a man who performs Salah (prayer) when at home, wearing a loincloth. He (the Imam) said, ‘He is to secure it with a handkerchief or turban to his neck when wearing.’”
Source: Shaykh Muḥammad b. Yaʿqūb al-Kulaynī