Language:
كتاب التهجد
19
Prayer at Night (Tahajjud)
(18)
Chapter: It is disliked to exaggerate in matters of worship
(18)
باب مَا يُكْرَهُ مِنَ التَّشْدِيدِ فِي الْعِبَادَةِ
Sahih al-Bukhari 1151

Narrated 'Aisha:

A woman from the tribe of Bani Asad was sitting with me and Allah's Apostle (p.b.u.h) came to my house and said, "Who is this?" I said, "(She is) So and so. She does not sleep at night because she is engaged in prayer." The Prophet (ﷺ) said disapprovingly: Do (good) deeds which is within your capacity as Allah never gets tired of giving rewards till you get tired of doing good deeds."

قَالَ وَقَالَ عَبْدُ اللَّهِ بْنِ مَسْلَمَةَ عَنْ مَالِكٍ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ قَالَتْ كَانَتْ عِنْدِي امْرَأَةٌ مِنْ بَنِي أَسَدٍ فَدَخَلَ عَلَىَّ رَسُولُ اللَّهِ صلى الله عليه وسلم فَقَالَ ‏"‏ مَنْ هَذِهِ ‏"‏‏.‏ قُلْتُ فُلاَنَةُ لاَ تَنَامُ بِاللَّيْلِ‏.‏ فَذُكِرَ مِنْ صَلاَتِهَا فَقَالَ ‏"‏ مَهْ عَلَيْكُمْ مَا تُطِيقُونَ مِنَ الأَعْمَالِ، فَإِنَّ اللَّهَ لاَ يَمَلُّ حَتَّى تَمَلُّوا ‏"‏‏.‏
Reference : Sahih al-Bukhari 1151
In-book reference : Book 19, Hadith 32
USC-MSA web (English) reference : Vol. 2, Book 21, Hadith 251
  (deprecated numbering scheme)