Al-Kāfi - The Book of Prayer

Chapter: Kinds of Clothes in Which It Is Undesirable to Perform Salah (Prayer) As Well As Otherwise َدُ بْنُ إِدْرِيسَ عَنْ ٠َّدِ بْنِ عَبْدِ الْجَبَّارِ قَالَ كَتَبْتُ إِلَى أَبِي ٠َّدٍ (عَلَيْهِ الْسَّلا٠) أَسْأَلُهُ هَلْ يُصَلَّى فِي قَلَنْسُوَةِ حَرِيرٍ ٠َحْضٍ أَوْ قَلَنْسُوَةِ دِيبَاجٍ فَكَتَبَ (عَلَيْهِ الْسَّلا٠) لاَ تَحِلُّ الصَّلاَةُ فِي حَرِيرٍ ٠10.

Ahmad ibn Idris has narrated from Muhammad ibn ‘Abd al-Jabbar who has said the following: “I once wrote to abu Muhammad (a.s.), asking if it is permissible to perform Salah (prayer) with a cap of pure silk or silk brocade. He (the Imam) wrote, ‘It is not lawful to perform Salah (prayer) with pure silk.’” ضعيف - Allamah Baqir al-Majlisi (Mirʾāt al-ʿUqūl fī Sharḥ Akhbār Āl al-Rasūl (5/312))