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.
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:3874 – Abū ʿAbdullāh al-Ḥāfiẓ > Abū al-ʿAbbās Muḥammad b. Yaʿqūb > Ibrāhīm b. Marzūq > Abū ʿĀṣim > ʿImrān al-Qaṭṭān

[Machine] Upon him, two prostrations of forgetfulness are required (in prayer).  

البيهقي:٣٨٧٤ – أَخْبَرَنَا أَبُو عَبْدِ اللهِ الْحَافِظُ ثنا أَبُو الْعَبَّاسِ مُحَمَّدُ بْنُ يَعْقُوبَ ثنا إِبْرَاهِيمُ بْنُ مَرْزُوقٍ ثنا أَبُو عَاصِمٍ عَنْ عِمْرَانَ الْقَطَّانِ عَنِ الْحَسَنِ فِيمَنْ نَسِيَ الْقُنُوتَ فِي صَلَاةِ الصُّبْحِ قَالَ

عَلَيْهِ سَجْدَتَا السَّهْوِ  

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Collected by Bayhaqī
bayhaqi:3875 – Abū al-ʿAbbās Muḥammad b. Yaʿqūb > al-ʿAbbās b. al-Walīd b. Mazyad from my father

[Machine] Upon him are two prostrations of forgetfulness.  

البيهقي:٣٨٧٥ – وأَخْبَرَنَا أَبُو عَبْدِ اللهِ ثنا أَبُو الْعَبَّاسِ مُحَمَّدُ بْنُ يَعْقُوبَ ثنا الْعَبَّاسُ بْنُ الْوَلِيدِ بْنِ مَزْيَدٍ أَخْبَرَنِي أَبِي عَنْ سَعِيدِ بْنِ عَبْدِ الْعَزِيزِ فِيمَنْ نَسِيَ الْقُنُوتَ فِي صَلَاةِ الصُّبْحِ قَالَ

عَلَيْهِ سَجْدَتَا السَّهْوِ