Muwatta Malik, Book 20, Hadith 797 (In-Book)

Yahya related to me from Malik from Ayyub ibn Musa that Abdullah ibn Umar once looked in the mirror for something that was irritating him while he was in ihram.

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ أَيُّوبَ بْنِ مُوسَى، أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ، نَظَرَ فِي الْمِرْآةِ لِشَكْوٍ كَانَ بِعَيْنَيْهِ وَهُوَ مُحْرِمٌ ‏.‏

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also referenced under: Book 20, Hadith 95 (USC-MSA)