كتاب صلاة المسافرين وقصرها
6  
The Book of Prayer - Travellers
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Chapter: The virtue of a deed that is done persistently, whether it be Qiyam al-Lail or anything else. The command to be moderate in worship, which means adopting what one can persist in. The command to the one who gets tired or weary when praying to stop until that feeling passes
(30)
باب فَضِيلَةِ الْعَمَلِ الدَّائِمِ مِنْ قِيَامِ اللَّيْلِ وَغَيْرِهِ ‏
Sahih Muslim 782 a

'A'isha reported that the Messenger of Allah (ﷺ) had a mat and he used it for making an apartment during the night and observed prayer in it, and the people began to pray with him, and he spread it (the mat) during the day time. The people crowded round him one night. He (the Holy Prophet) then said:

O people, perform such acts as you are capable of doing, for Allah does not grow weary but you will get tired. The acts most pleasing to Allah are those which are done continuously, even if they are small. And it was the habit of the members of Muhammad's (ﷺ) household that whenever they did an act they did it continuously.
وَحَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا عَبْدُ الْوَهَّابِ، - يَعْنِي الثَّقَفِيَّ - حَدَّثَنَا عُبَيْدُ اللَّهِ، عَنْ سَعِيدِ بْنِ أَبِي سَعِيدٍ، عَنْ أَبِي سَلَمَةَ، عَنْ عَائِشَةَ، أَنَّهَا قَالَتْ كَانَ لِرَسُولِ اللَّهِ صلى الله عليه وسلم حَصِيرٌ وَكَانَ يُحَجِّرُهُ مِنَ اللَّيْلِ فَيُصَلِّي فِيهِ فَجَعَلَ النَّاسُ يُصَلُّونَ بِصَلاَتِهِ وَيَبْسُطُهُ بِالنَّهَارِ فَثَابُوا ذَاتَ لَيْلَةٍ فَقَالَ ‏ "‏ يَا أَيُّهَا النَّاسُ عَلَيْكُمْ مِنَ الأَعْمَالِ مَا تُطِيقُونَ فَإِنَّ اللَّهَ لاَ يَمَلُّ حَتَّى تَمَلُّوا وَإِنَّ أَحَبَّ الأَعْمَالِ إِلَى اللَّهِ مَا دُووِمَ عَلَيْهِ وَإِنْ قَلَّ ‏"‏ ‏.‏ وَكَانَ آلُ مُحَمَّدٍ صلى الله عليه وسلم إِذَا عَمِلُوا عَمَلاً أَثْبَتُوهُ ‏.‏
Reference : Sahih Muslim 782a
In-book reference : Book 6, Hadith 255
USC-MSA web (English) reference : Book 4, Hadith 1710
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