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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
ahmad:4282 – Ibn Idrīs > al-Ḥasan b. ʿUbaydullāh > Ibrāhīm > ʿAlqamah > ʿAbdullāh

[Machine] The Prophet ﷺ prayed five (units of prayer) with them, then he added an extra unit. Some people started whispering to each other, so they said to him, "O Messenger of Allah! You prayed five (units of prayer) and then added an extra unit." So he performed two prostrations with them and said, "I am only a human being, I forget just as you forget."  

أحمد:٤٢٨٢ – حَدَّثَنَا ابْنُ إِدْرِيسَ قَالَ سَمِعْتُ الْحَسَنَ بْنَ عُبَيْدِ اللهِ يَذْكُرُ عَنْ إِبْرَاهِيمَ عَنْ عَلْقَمَةَ أَنَّهُ أَخْبَرَهُمْ عَنْ عَبْدِ اللهِ

أَنَّ رَسُولَ اللهِ ﷺ صَلَّى بِهِمْ خَمْسًا ثُمَّ انْفَتَلَ فَجَعَلَ بَعْضُ الْقَوْمِ يُوَشْوِشُ إِلَى بَعْضٍ فَقَالُوا لَهُ يَا رَسُولَ اللهِ صَلَّيْتَ خَمْسًا فَانْفَتَلَ فَسَجَدَ بِهِمْ سَجْدَتَيْنِ وَسَلَّمَ وَقَالَ إِنَّمَا أَنَا بَشَرٌ أَنْسَى كَمَا تَنْسَوْنَ  

See similar narrations below:

Collected by Abū Dāwūd
abudawud:1022 – [Chain 1] Naṣr b. ʿAlī > Jarīr [Chain 2] Yūsuf b. Mūsá > Jarīr And Hadhā Ḥadīth Yūsuf > al-Ḥasan b. ʿUbaydullāh > Ibrāhīm b. Sūwayd > ʿAlqamah

Messenger of Allah, has (the number of the rak’ahs of) the prayer been increased ? he said : No. they said; you have offered five rak’ahs of prayer. He then turned away and performed two prostrations, and afterwards gave the salutation. He then said : I am only a human being, I forget, as you forget.  

أبو داود:١٠٢٢ – حَدَّثَنَا نَصْرُ بْنُ عَلِيٍّ أَخْبَرَنَا جَرِيرٌ ح وَحَدَّثَنَا يُوسُفُ بْنُ مُوسَى حَدَّثَنَا جَرِيرٌ وَهَذَا حَدِيثُ يُوسُفَ عَنِ الْحَسَنِ بْنِ عُبَيْدِ اللَّهِ عَنْ إِبْرَاهِيمَ بْنِ سُوَيْدٍ عَنْ عَلْقَمَةَ قَالَ قَالَ

عَبْدُ اللَّهِ صَلَّى بِنَا رَسُولُ اللَّهِ ﷺ خَمْسًا فَلَمَّا انْفَتَلَ تَوَشْوَشَ الْقَوْمُ بَيْنَهُمْ فَقَالَ مَا شَأْنُكُمْ قَالُوا يَا رَسُولَ اللَّهِ هَلْ زِيدَ فِي الصَّلاَةِ قَالَ لاَ قَالُوا فَإِنَّكَ صَلَّيْتَ خَمْسًا فَانْفَتَلَ فَسَجَدَ سَجْدَتَيْنِ ثُمَّ سَلَّمَ ثُمَّ قَالَ إِنَّمَا أَنَا بَشَرٌ أَنْسَى كَمَا تَنْسَوْنَ