2. Ṣalāh (Prayer)

٢۔ كِتَابُ الصَّلَاةِ

2.385 [Machine] Placement of the right hand over the left in prayer

٢۔٣٨٥ وَضْعُ الْيَمِينِ عَلَى الشِّمَالِ فِي الصَّلَاةِ

nasai-kubra:963Sūwayd b. Naṣr al-Marwazī > ʿAbdullāh b. al-Mubārak > Mūsá b. ʿUmayr al-ʿAnbarī And Qays > ʿAlqamah b. Wāʾil from his father

"Alqamah bin Wa'il told us that his father said: "I saw the Messenger of Allah ﷺ, when he was standing in prayer, holding his left hand with his right.'" (Using translation from Nasāʾī 887)  

الكبرى للنسائي:٩٦٣أَخْبَرَنَا سُوَيْدُ بْنُ نَصْرٍ الْمَرْوَزِيِّ قَالَ أَخْبَرَنَا عَبْدُ اللهِ بْنُ الْمُبَارَكِ عَنْ مُوسَى بْنِ عُمَيْرٍ الْعَنْبَرِيِّ وَقَيْسٍ قَالَا حَدَّثَنَا عَلْقَمَةُ بْنُ وَائِلٍ عَنْ أَبِيهِ قَالَ

«رَأَيْتُ رَسُولَ اللهِ ﷺ إِذَا كَانَ قَائِمًا فِي الصَّلَاةِ قَبَضَ بِيَمِينِهِ عَلَى شِمَالِهِ»