(4) باب الوضوء
Narrated Anas (rad):
The Prophet (ﷺ) saw a man on whose foot appeared a portion like the size of a nail which was not touched by water. He then said, "Go back and perform your Wudu properly." [Reported by Abu Da'ud and An-Nasa'i]. (DE)
Reference (DE): Bulugh al-Maram 55 (DE)
In-book reference (DE): Book 1, Hadith 64 (DE)
English translation (DE): Book 1, Hadith 60 (DE)