Narrated by:Ibn 'Umar that
It was narrated from Ibn 'Umar that :The Prophet [SAW] saw a boy, part of whose head had been shaven and part had been left. He forbade that and said: "Shave all of it, or leave all of it."
أَخْبَرَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، أَنْبَأَنَا عَبْدُ الرَّزَّاقِ، قَالَ أَنْبَأَنَا مَعْمَرٌ، عَنْ أَيُّوبَ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، أَنَّ النَّبِيَّ صلى الله عليه وسلم رَأَى صَبِيًّا حَلَقَ بَعْضَ رَأْسِهِ وَتَرَكَ بَعْضَ فَنَهَى عَنْ ذَلِكَ وَقَالَ " احْلِقُوهُ كُلَّهُ أَوِ اتْرُكُوهُ كُلَّهُ " .
Nesai
The Book of Adornment • Hadith 5048