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.
muslim:468aMuḥammad b. ʿAbdullāh b. Numayr from my father > ʿAmr b. ʿUthmān > Mūsá b. Ṭalḥah

The Apostle of Allah ﷺ said to him: Lead your people in prayer. I said: Messenger of Allah. I perceive something (disturbing) in my soul. He (the Holy Prophet) asked me to draw near him and making me sit down in front of him he placed his hand on my breast between my nipples. and then, telling me to turn round, he placed it on my back between my shoulders. He then said: Act as an Imam for your people. He who acts as Imam of the people, he must be brief, for among them are the aged, among them are the sick, among them are the weak, and among them are the people who have business to attend. But when any of you prays alone, he may pray as he likes.  

مسلم:٤٦٨aحَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ بْنِ نُمَيْرٍ حَدَّثَنَا أَبِي حَدَّثَنَا عَمْرُو بْنُ عُثْمَانَ حَدَّثَنَا مُوسَى بْنُ طَلْحَةَ حَدَّثَنِي عُثْمَانُ بْنُ أَبِي الْعَاصِ الثَّقَفِيُّ

أَنَّ النَّبِيَّ ﷺ قَالَ لَهُ أُمَّ قَوْمَكَ قَالَ قُلْتُ يَا رَسُولَ اللَّهِ إِنِّي أَجِدُ فِي نَفْسِي شَيْئًا قَالَ ادْنُهْ فَجَلَّسَنِي بَيْنَ يَدَيْهِ ثُمَّ وَضَعَ كَفَّهُ فِي صَدْرِي بَيْنَ ثَدْيَىَّ ثُمَّ قَالَ تَحَوَّلْ فَوَضَعَهَا فِي ظَهْرِي بَيْنَ كَتِفَىَّ ثُمَّ قَالَ أُمَّ قَوْمَكَ فَمَنْ أَمَّ قَوْمًا فَلْيُخَفِّفْ فَإِنَّ فِيهِمُ الْكَبِيرَ وَإِنَّ فِيهِمُ الْمَرِيضَ وَإِنَّ فِيهِمُ الضَّعِيفَ وَإِنَّ فِيهِمْ ذَا الْحَاجَةِ وَإِذَا صَلَّى أَحَدُكُمْ وَحْدَهُ فَلْيُصَلِّ كَيْفَ شَاءَ  


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Collected by Bayhaqī, Suyūṭī
bayhaqi:5278Abū ʿAbdullāh al-Ḥāfiẓ > Abū Jaʿfar Muḥammad b. Ṣāliḥ b. Hāniʾ > Aḥmad b. Naṣr > Abū Nuʿaym > ʿAmr b. ʿUthmān > Muḥammad b. Yaʿqūb Imlāʾ > al-Ḥasan b. Sufyān > Muḥammad b. ʿAbdullāh b. Numayr from my father > ʿAmr b. ʿUthmān > Mūsá b. Ṭalḥah

The Apostle of Allah ﷺ said to him: Lead your people in prayer. I said: Messenger of Allah. I perceive something (disturbing) in my soul. He (the Holy Prophet) asked me to draw near him and making me sit down in front of him he placed his hand on my breast between my nipples. and then, telling me to turn round, he placed it on my back between my shoulders. He then said: Act as an Imam for your people. He who acts as Imam of the people, he must be brief, for among them are the aged, among them are the sick, among them are the weak, and among them are the people who have business to attend. But when any of you prays alone, he may pray as he likes. (Using translation from Muslim 468a)   

البيهقي:٥٢٧٨أَخْبَرَنَا أَبُو عَبْدِ اللهِ الْحَافِظُ ثنا أَبُو جَعْفَرٍ مُحَمَّدُ بْنُ صَالِحِ بْنِ هَانِئٍ ثنا أَحْمَدُ بْنُ نَصْرٍ ثنا أَبُو نُعَيْمٍ ثنا عَمْرُو بْنُ عُثْمَانَ قَالَ وَحَدَّثَنَا مُحَمَّدُ بْنُ يَعْقُوبَ إِمْلَاءً وَاللَّفْظُ لَهُ ثنا الْحَسَنُ بْنُ سُفْيَانَ ثنا مُحَمَّدُ بْنُ عَبْدِ اللهِ بْنِ نُمَيْرٍ ثنا أَبِي ثنا عَمْرُو بْنُ عُثْمَانَ ثنا مُوسَى بْنُ طَلْحَةَ ثنا عُثْمَانُ بْنُ أَبِي الْعَاصِ الثَّقَفِيُّ

أَنَّ النَّبِيَّ ﷺ قَالَ لَهُ أُمَّ قَوْمَكَ فَقُلْتُ يَا رَسُولَ اللهِ إِنِّي أَجِدُ فِي نَفْسِي شَيْئًا قَالَ ادْنُهْ فَأَجْلَسَنِي بَيْنَ يَدَيْهِ ثُمَّ وَضَعَ كَفَّهُ فِي صَدْرِي بَيْنَ ثَدْيِيَّ ثُمَّ قَالَ تَحَوَّلْ فَوَضَعَهُمَا فِي ظَهْرِي بَيْنَ كَتِفِيَّ ثُمَّ قَالَ أُمَّ قَوْمَكَ فَمَنْ أَمَّ قَوْمًا فَلْيُخَفِّفْ فَإِنَّ فِيهِمُ الْكَبِيرَ وَإِنَّ فِيهِمُ الصَّغِيرَ وَإِنَّ فِيهِمُ الْمَرِيضَ وَإِنَّ فِيهِمْ ذَا الْحَاجَةِ فَإِذَا صَلَّى أَحَدُكُمْ فَلْيُصَلِّ كَيْفَ شَاءَ  

رَوَاهُ مُسْلِمٌ فِي الصَّحِيحِ عَنْ مُحَمَّدِ بْنِ عَبْدِ اللهِ بْنِ نُمَيْرٍ
suyuti:4385a
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السيوطي:٤٣٨٥a

"أُمُّ قَوْمَكَ؛ فمن أمَّ قَوْمًا فَليُخَفِّف؛ فإنَّ فيهم الكبيرَ، وإن فيهم المريضَ، وإن فيهم الضعيف، وإن فيهم ذا الحاجة. فإذا صلى أَحدُكم وحده فليُصل كيفَ شاء".  

من، [م] مسلم عن عثمان بن أبي العاص