(17) باب فَضْلِ الطُّهُورِ بِاللَّيْلِ وَالنَّهَارِ وَفَضْلِ الصَّلاَةِ بَعْدَ الْوُضُوءِ بِاللَّيْلِ وَالنَّهَارِ
Narrated Abu Huraira:
At the time of the Fajr prayer the Prophet (ﷺ) asked Bilal, "Tell me of the best deed you did after embracing Islam, for I heard your footsteps in front of me in Paradise." Bilal replied, "I did not do anything worth mentioning except that whenever I performed ablution during the day or night, I prayed after that ablution as much as was written for me."
Reference: Sahih al-Bukhari 1149
In-book reference: Book 19, Hadith 30
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 2, Book 21, Hadith 250