(29) باب غَسْلِ الأَعْقَابِ
Narrated Muhammad Ibn Ziyad:
I heard Abu Huraira saying as he passed by us while the people were performing ablution from a utensil containing water, "Perform ablution perfectly and thoroughly for Abul-Qasim (the Prophet) said, 'Save your heels from the Hell-fire.' "
Reference: Sahih al-Bukhari 165
In-book reference: Book 4, Hadith 31
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 1, Book 4, Hadith 166