Al-Adab Al-Mufrad, Book 43, Hadith 1051 (English) ⓘ

Anas said that he was ten years old when the Messenger of Allah, may Allah bless him and grant him peace, came to Madina. He said, "My mothers decided that I would serve him and I served him for ten years. He died when I was twenty. I am the person who knows best about the business of the veil. The first instance that was revealed occurred when the Messenger of Allah, may Allah bless him and grant him peace, built a room for Zaynab bint Jahsh. He celebrated the wedding there, invited the people who came, ate and then left. A group remained with the Prophet, may Allah bless him and grant him peace. They stayed for a long time and then the Prophet went out and I went out hoping that they would leave. He walked and I walked with him until he came to the threshold of 'A'isha's room. Then, thinking that they would have left, he returned and I returned with him. He went to Zaynab but they were still sitting there. He left again and I left with him until he once more reached the threshold of 'A'isha's room. When he thought that they would have gone, he went back again and I went back with him. This time they had indeed left. The Prophet, may Allah bless him and grant him peace, then put up a curtain between me and him, and the veil was revealed."

حَدَّثَنَا عَبْدُ اللهِ بْنُ صَالِحٍ قَالَ‏:‏ حَدَّثَنِي اللَّيْثُ قَالَ‏:‏ حَدَّثَنِي عُقَيْلٌ، عَنِ ابْنِ شِهَابٍ قَالَ‏:‏ أَخْبَرَنِي أَنَسٌ، أَنَّهُ كَانَ ابْنَ عَشْرِ سِنِينَ مَقْدَمَ رَسُولِ اللهِ صلى الله عليه وسلم الْمَدِينَةَ، فَكُنَّ أُمَّهَاتِي يُوَطِّوَنَّنِي عَلَى خِدْمَتِهِ، فَخَدَمْتُهُ عَشْرَ سِنِينَ، وَتُوُفِّيَ وَأَنَا ابْنُ عِشْرِينَ، فَكُنْتُ أَعْلَمَ النَّاسِ بِشَأْنِ الْحِجَابِ، فَكَانَ أَوَّلُ مَا نَزَلَ مَا ابْتَنَى رَسُولُ اللهِ صلى الله عليه وسلم بِزَيْنَبَ بِنْتِ جَحْشٍ، أَصْبَحَ بِهَا عَرُوسًا، فَدَعَى الْقَوْمَ فَأَصَابُوا مِنَ الطَّعَامِ، ثُمَّ خَرَجُوا، وَبَقِيَ رَهْطٌ عِنْدَ النَّبِيِّ صلى الله عليه وسلم، فَأَطَالُوا الْمُكْثَ، فَقَامَ فَخَرَجَ وَخَرَجْتُ لِكَيْ يَخْرُجُوا، فَمَشَى فَمَشَيْتُ مَعَهُ، حَتَّى جَاءَ عَتَبَةَ حُجْرَةِ عَائِشَةَ، ثُمَّ ظَنَّ أَنَّهُمْ خَرَجُوا، فَرَجَعَ وَرَجَعْتُ مَعَهُ حَتَّى دَخَلَ عَلَى زَيْنَبَ، فَإِذَا هُمْ جُلُوسٌ، فَرَجَعَ وَرَجَعْتُ حَتَّى بَلَغَ عَتَبَةَ حُجْرَةِ عَائِشَةَ، وَظَنَّ أَنَّهُمْ خَرَجُوا، فَرَجَعَ وَرَجَعْتُ مَعَهُ، فَإِذَا هُمْ قَدْ خَرَجُوا، فَضَرَبَ النَّبِيُّ صلى الله عليه وسلم بَيْنِي وَبَيْنَهُ السِّتْرَ، وَأَنْزَلَ الْحِجَابَ‏.‏