Al-Kāfi
Hadith 673أَحْمَدُ بْنُ مُحَمَّدِ بْنِ أَبِي نَصْرٍ قَالَ سَأَلْتُ أَبَا الْحَسَنِ الرِّضَا ( عليه السلام ) قُلْتُ لَهُ أَصْلَحَكَ اللَّهُ كَيْفَ الْمُلَاعَنَةُ قَالَ فَقَالَ يَقْعُدُ الْإِمَامُ وَ يَجْعَلُ ظَهْرَهُ إِلَى الْقِبْلَةِ وَ يَجْعَلُ الرَّجُلَ عَنْ يَمِينِهِ وَ الْمَرْأَةَ عَنْ يَسَارِهِ .
11. Ahmad ibn Muhammad from ibn abu Nasr has said the following: “I once asked al-Rida’ (a.s.), saying, ‘I pray to Allah to keep you well, how is al-Li‘an (condemnation) completed?’ He (the Imam) said, ‘The Imam sits down with his back to the al-Qiblah (al-Ka‘bah) and keeps the man on his right and the woman on his left.’”