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nasai-kubra:1169 – Sūwayd b. Naṣr > ʿAbdullāh > Shuʿbah > 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)  

الكبرى للنسائي:١١٦٩ – أَخْبَرَنَا سُوَيْدُ بْنُ نَصْرٍ قَالَ أَخْبَرَنَا عَبْدُ اللهِ عَنْ شُعْبَةَ عَنِ الْحَكَمِ قَالَ سَمِعْتُ أَبَا وَائِلٍ يَقُولُ قَالَ

عَبْدُ اللهِ «مَنْ أَوْهَمَ فِي صَلَاتِهِ فَلْيَتَحَرَّ الصَّوَابَ ثُمَّ لْيَسْجُدْ سَجْدَتَيْنِ بَعْدَمَا يَفْرُغُ وَهُوَ جَالِسٌ»  

See similar narrations below:

Collected by Nasāʾī, Ṭabarānī
nasai:1241 – Muḥammad b. ʿAbdullāh b. al-Mubārak al-Mukharramī > Wakīʿ > Misʿar > Manṣūr > Ibrāhīm > ʿAlqamah > ʿAbdullāh

"The Messenger of Allah ﷺ said: 'If one of you is not sure about his prayer, let him estimate and prostrate twice after he has finished."  

النسائي:١٢٤١ – أَخْبَرَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ بْنِ الْمُبَارَكِ الْمُخَرَّمِيُّ قَالَ حَدَّثَنَا وَكِيعٌ عَنْ مِسْعَرٍ عَنْ مَنْصُورٍ عَنْ إِبْرَاهِيمَ عَنْ عَلْقَمَةَ عَنْ عَبْدِ اللَّهِ قَالَ

قَالَ رَسُولُ اللَّهِ ﷺ إِذَا شَكَّ أَحَدُكُمْ فِي صَلاَتِهِ فَلْيَتَحَرَّ وَيَسْجُدْ سَجْدَتَيْنِ بَعْدَ مَا يَفْرُغُ  

nasai:1245 – Sūwayd b. Naṣr > ʿAbdullāh > Shuʿbah > 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."  

النسائي:١٢٤٥ – أَخْبَرَنَا سُوَيْدُ بْنُ نَصْرٍ قَالَ أَنْبَأَنَا عَبْدُ اللَّهِ عَنْ شُعْبَةَ عَنِ الْحَكَمِ قَالَ سَمِعْتُ أَبَا وَائِلٍ يَقُولُ قَالَ

عَبْدُ اللَّهِ مَنْ أَوْهَمَ فِي صَلاَتِهِ فَلْيَتَحَرَّ الصَّوَابَ ثُمَّ يَسْجُدْ سَجْدَتَيْنِ بَعْدَ مَا يَفْرُغُ وَهُوَ جَالِسٌ  

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»