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Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
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  

See similar narrations below:

Collected by Nasāʾī's Kubrá
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»