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nasai-kubra:1170 – Sūwayd b. Naṣr > ʿAbdullāh > Misʿar > al-Ḥakam > Abū Wāʾil > ʿAbdullāh

"Whoever has doubt, or is not sure, let him estimate what is correct, then let him prostrate twice." (Using translation from Nasāʾī 1246)  

الكبرى للنسائي:١١٧٠ – أَخْبَرَنَا سُوَيْدُ بْنُ نَصْرٍ قَالَ أَخْبَرَنَا عَبْدُ اللهِ عَنْ مِسْعَرٍ عَنِ الْحَكَمِ عَنْ أَبِي وَائِلٍ عَنْ عَبْدِ اللهِ قَالَ

«مَنْ شَكَّ أَوْ أَوْهَمَ فَلْيَتَحَرَّ ثُمَّ لِيَسْجُدَ سَجْدَتَيْنِ»  

See similar narrations below:

Collected by Nasāʾī, Ṭabarānī
nasai:1246 – Sūwayd b. Naṣr > ʿAbdullāh > Misʿar > al-Ḥakam > Abū Wāʾil > ʿAbdullāh

"Whoever has doubt, or is not sure, let him estimate what is correct, then let him prostrate twice."  

النسائي:١٢٤٦ – أَخْبَرَنَا سُوَيْدُ بْنُ نَصْرٍ قَالَ أَنْبَأَنَا عَبْدُ اللَّهِ عَنْ مِسْعَرٍ عَنِ الْحَكَمِ عَنْ أَبِي وَائِلٍ عَنْ عَبْدِ اللَّهِ قَالَ

مَنْ شَكَّ أَوْ أَوْهَمَ فَلْيَتَحَرَّ الصَّوَابَ ثُمَّ لْيَسْجُدْ سَجْدَتَيْنِ  

tabarani:9183 – ʿAlī b. ʿAbd al-ʿAzīz > Abū Nuʿaym > Misʿar > al-Ḥakam > Abū Wāʾil

"Whoever us not sure about his prayer, then let him estimate what is correct, then let him prostrate twice after he finished his prayer, while he is sitting." (Using translation from Nasāʾī 1245)   

الطبراني:٩١٨٣ – حَدَّثَنَا عَلِيُّ بْنُ عَبْدِ الْعَزِيزِ ثنا أَبُو نُعَيْمٍ ثنا مِسْعَرٌ عَنِ الْحَكَمِ عَنْ أَبِي وَائِلٍ قَالَ قَالَ

عَبْدُ اللهِ «مَنْ شَكَّ أَوْ وَهِمَ فِي صَلَاتِهِ فَلْيَتَحَرَّ ثُمَّ يَسْجُدْ سَجْدَتَيْنِ»