Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
nasai-kubra:1171Sūwayd > ʿAbdullāh > Ibn ʿAwn > Ibrāhīm

"They used to say: 'If one is not sure of what he estimates is correct, then prostrate twice.'" (Using translation from Nasāʾī 1247)  

الكبرى للنسائي:١١٧١أَخْبَرَنَا سُوَيْدُ قَالَ أَخْبَرَنَا عَبْدُ اللهِ عَنِ ابْنِ عَوْنٍ عَنْ إِبْرَاهِيمَ قَالَ

كَانُوا يَقُولُونَ «إِذَا أَوْهَمَ يَتَحَرَّى الصَّوَابَ ثُمَّ يَسْجُدَ سَجْدَتَيْنِ»  


See similar narrations below:

Collected by Nasāʾī
nasai:1246Sūwayd 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:١٢٤٦أَخْبَرَنَا 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  

nasai:1247Sūwayd b. Naṣr > ʿAbdullāh > Ibn ʿAwn > Ibrāhīm

"They used to say: 'If one is not sure of what he estimates is correct, then prostrate twice.'"  

النسائي:١٢٤٧أَخْبَرَنَا سُوَيْدُ بْنُ نَصْرٍ قَالَ أَنْبَأَنَا عَبْدُ اللَّهِ عَنِ ابْنِ عَوْنٍ عَنْ إِبْرَاهِيمَ قَالَ

كَانُوا يَقُولُونَ إِذَا أَوْهَمَ يَتَحَرَّى الصَّوَابَ ثُمَّ يَسْجُدُ سَجْدَتَيْنِ