Sahih al-Bukhari 6462

Arabic

حَدَّثَنَا قُتَيْبَةُ، عَنْ مَالِكٍ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ، أَنَّهَا قَالَتْ كَانَ أَحَبُّ الْعَمَلِ إِلَى رَسُولِ اللَّهِ صلى الله عليه وسلم الَّذِي يَدُومُ عَلَيْهِ صَاحِبُهُ‏.‏

English translation

Narrated `Aisha:The most beloved action to Allah's Messenger (ﷺ) was that whose doer did it continuously and regularly

Reference: Sahih al-Bukhari 6462, Book of To make the Heart Tender (Ar-Riqaq). English translation by Dr. Muhammad Muhsin Khan.