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
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باب فَضِيلَةِ الْعَمَلِ الدَّائِمِ مِنْ قِيَامِ اللَّيْلِ وَغَيْرِهِ ‏
Sahih Muslim 783 a

Alqama reported:

I asked 'A'isha, the mother of the believers, saying O mother of the believers, how did the Messenger of Allah (ﷺ) act? Did he choose a particular act for a particular day? She said: No. He act was continuous, and who amongst you is capable of doing what the Messenger of Allah (ﷺ) did?
وَحَدَّثَنَا زُهَيْرُ بْنُ حَرْبٍ، وَإِسْحَاقُ بْنُ إِبْرَاهِيمَ، قَالَ زُهَيْرٌ حَدَّثَنَا جَرِيرٌ، عَنْ مَنْصُورٍ، عَنْ إِبْرَاهِيمَ، عَنْ عَلْقَمَةَ، قَالَ سَأَلْتُ أُمَّ الْمُؤْمِنِينَ عَائِشَةَ قَالَ قُلْتُ يَا أُمَّ الْمُؤْمِنِينَ كَيْفَ كَانَ عَمَلُ رَسُولِ اللَّهِ صلى الله عليه وسلم هَلْ كَانَ يَخُصُّ شَيْئًا مِنَ الأَيَّامِ قَالَتْ لاَ ‏.‏ كَانَ عَمَلُهُ دِيمَةً وَأَيُّكُمْ يَسْتَطِيعُ مَا كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يَسْتَطِيعُ .
Reference : Sahih Muslim 783a
In-book reference : Book 6, Hadith 257
USC-MSA web (English) reference : Book 4, Hadith 1712
  (deprecated numbering scheme)