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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
malik:8-12 – Mālik > ʿAfīf al-Sahmī > a man Min Banī Asad > Saʾal Abū Ayyūb al-Anṣārī

Yahya related to me from Malik from Afif as-Sahmi that a man from the tribe of Bani Asad asked Abu Ayyub al-Ansari. "Sometimes I pray in my house, and then come to the mosque and find the imam praying. Should I pray with him?" Abu Ayyub said, "Yes, pray with him, for some one who does so has the reward of the group, or the equivalent of the reward of the group."  

مالك:٨-١٢ – وَحَدَّثَنِي عَنْ مَالِكٍ عَنْ عَفِيفٍ السَّهْمِيِّ عَنْ رَجُلٍ مِنْ بَنِي أَسَدٍ أَنَّهُ سَأَلَ أَبَا أَيُّوبَ الأَنْصَارِيَّ

فَقَالَ إِنِّي أُصَلِّي فِي بَيْتِي ثُمَّ آتِي الْمَسْجِدَ فَأَجِدُ الإِمَامَ يُصَلِّي أَفَأُصَلِّي مَعَهُ فَقَالَ أَبُو أَيُّوبَ نَعَمْ فَصَلِّ مَعَهُ فَإِنَّ مَنْ صَنَعَ ذَلِكَ فَإِنَّ لَهُ سَهْمَ جَمْعٍ أَوْ مِثْلَ سَهْمِ جَمْعٍ  

See similar narrations below:

Collected by Mālik, Bayhaqī
malik:8-11 – Mālik > Yaḥyá b. Saʿīd > a man Saʾal Saʿīd b. al-Musayyab

Yahya related to me from Malik from Yahya ibn Said that a man asked Said ibn al-Musayyab, "I pray in my house, and then I come to the mosque and find the imam praying. Should I pray with him?" Said said, "Yes," and the man said, "Which of them is my prayer?" Said said, "Are you the one to decide that? That is up to Allah."  

مالك:٨-١١ – وَحَدَّثَنِي عَنْ مَالِكٍ عَنْ يَحْيَى بْنِ سَعِيدٍ أَنَّ رَجُلاً سَأَلَ سَعِيدَ بْنَ الْمُسَيَّبِ

فَقَالَ إِنِّي أُصَلِّي فِي بَيْتِي ثُمَّ آتِي الْمَسْجِدَ فَأَجِدُ الإِمَامَ يُصَلِّي أَفَأُصَلِّي مَعَهُ فَقَالَ سَعِيدٌ نَعَمْ فَقَالَ الرَّجُلُ فَأَيُّهُمَا صَلاَتِي فَقَالَ سَعِيدٌ أَوَأَنْتَ تَجْعَلُهُمَا إِنَّمَا ذَلِكَ إِلَى اللَّهِ  

bayhaqi:3642 – Abū Aḥmad al-Mihrajānī > Abū Bakr b. Ḥafṣ > Muḥammad b. Ibrāhīm > Ibn Bukayr > Mālik > ʿAfīf b. ʿUmar al-Sahmī > a man from Banī Asad

[Machine] "I pray in my house, then I go to the mosque and find the Imam praying, so I pray with him?" Abu Ayyub replied, "Yes, whoever does that will have the reward of their prayer multiplied or equivalent to the reward of praying in congregation."  

البيهقي:٣٦٤٢ – أَخْبَرَنَا أَبُو أَحْمَدَ الْمِهْرَجَانِيُّ أنبأ أَبُو بَكْرِ بْنُ حَفْصٍ ثنا مُحَمَّدُ بْنُ إِبْرَاهِيمَ ثنا ابْنُ بُكَيْرٍ ثنا مَالِكٌ عَنْ عَفِيفِ بْنِ عُمَرَ السَّهْمِيِّ عَنْ رَجُلٍ مِنْ بَنِي أَسَدٍ أَنَّهُ سَأَلَ أَبَا أَيُّوبَ الْأَنْصَارِيَّ فَقَالَ

إِنِّي أُصَلِّي فِي بَيْتِي ثُمَّ آتِي الْمَسْجِدَ فَأَجِدُ الْإِمَامَ يُصَلِّي فَأُصَلِّي مَعَهُ؟ فَقَالَ أَبُو أَيُّوبَ نَعَمْ مَنْ صَنَعَ ذَلِكَ فَإِنَّ لَهُ سَهْمُ جَمْعٍ أَوْ مِثْلُ سَهْمِ جَمْعٍ