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nasai-kubra:11354 – Muḥammad b. al-Muthanná > Khālid > Ḥumayd > Anas

I said, "O Messenger of Allah ﷺ! Good and bad persons enter upon you, so I suggest that you order the mothers of the Believers (i.e. your wives) to observe veils." Then Allah revealed the Verses of Al- Hijab. (Using translation from Bukhārī 4790)   

الكبرى للنسائي:١١٣٥٤ – أَخْبَرَنَا مُحَمَّدُ بْنُ الْمُثَنَّى قَالَ حَدَّثَنَا خَالِدٌ قَالَ حَدَّثَنَا حُمَيْدٌ أَنَّ أَنَسًا قَالَ

قَالَ عُمَرُ قُلْتُ «يَا رَسُولَ اللهِ يَدْخُلُ عَلَيْكَ الْبَرُّ وَالْفَاجِرُ فَلَوْ حَجَبْتَ أُمَّهَاتِ الْمُؤْمِنِينَ فَأَنْزَلَ اللهُ ﷻ آيَةَ الْحِجَابِ»  

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Collected by Bukhārī
bukhari:4790 – Musaddad > Yaḥyá > Ḥumayd > Anas > ʿUmar

I said, "O Messenger of Allah ﷺ! Good and bad persons enter upon you, so I suggest that you order the mothers of the Believers (i.e. your wives) to observe veils." Then Allah revealed the Verses of Al- Hijab.  

البخاري:٤٧٩٠ – حَدَّثَنَا مُسَدَّدٌ عَنْ يَحْيَى عَنْ حُمَيْدٍ عَنْ أَنَسٍ قَالَ قَالَ

عُمَرُ ؓ قُلْتُ يَا رَسُولَ اللَّهِ يَدْخُلُ عَلَيْكَ الْبَرُّ وَالْفَاجِرُ فَلَوْ أَمَرْتَ أُمَّهَاتِ الْمُؤْمِنِينَ بِالْحِجَابِ فَأَنْزَلَ اللَّهُ آيَةَ الْحِجَابِ