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Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
bayhaqi:657 – Abū Muḥammad ʿAbdullāh b. Yaḥyá b. ʿAbd al-Jabbār al-Sukkarī > Ismāʿīl b. Muḥammad al-Ṣaffār > Saʿdān b. Naṣr > Abū Muʿāwiyah > Abū Jaʿfar al-Rāzī > Yaḥyá al-Bakkāʾ

[Machine] I saw Ibn Umar insert his hand into his armpit while he was praying, and then he continued his prayer.  

البيهقي:٦٥٧ – أَخْبَرَنَاهُ أَبُو مُحَمَّدٍ عَبْدُ اللهِ بْنُ يَحْيَى بْنِ عَبْدِ الْجَبَّارِ السُّكَّرِيُّ بِبَغْدَادَ ثنا إِسْمَاعِيلُ بْنُ مُحَمَّدٍ الصَّفَّارُ ثنا سَعْدَانُ بْنُ نَصْرٍ ثنا أَبُو مُعَاوِيَةَ عَنْ أَبِي جَعْفَرٍ الرَّازِيِّ عَنْ يَحْيَى الْبَكَّاءِ قَالَ

رَأَيْتُ ابْنَ عُمَرَ أَدْخَلَ يَدَهُ فِي إِبْطِهِ وَهُوَ فِي الصَّلَاةِ ثُمَّ مَضَى فِي صَلَاتِهِ