وَعَنْ أَنَسٍ رضى الله عنه
قَالَ: «رَأَى اَلنَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ رَجُلًا، وَفِي قَدَمِهِ مِثْلُ اَلظُّفْرِ لَمْ يُصِبْهُ اَلْمَاءُ. فَقَالَ: «اِرْجِعْ فَأَحْسِنْ وُضُوءَكَ»
The Prophet (sallallahu alayhi wa sallam) 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.”.