Hadith 7.95

7.95:
Narrated Anas bin Malik: I was ten years old when Allah's
Apostle arrived at Medina. My mother and aunts used to urge me
to serve the Prophet regularly, and I served him for ten
years. When the Prophet died I was twenty years old, and I
knew about the order of Al−Hijab (veiling of ladies) more than
any other person when it was revealed. It was revealed for the
first time when Allah's Apostle had consummated his marriage
with Zainab bint Jahsh. When the day dawned, the Prophet was a
bridegroom and he invited the people to a banquet, so they
came, ate, and then all left except a few who remained with
the Prophet for a long time. The Prophet got up and went out,
and I too went out with him so that those people might leave
too. The Prophet proceeded and so did I, till he came to the
threshold of `Aisha's dwelling place. Then thinking that these
people have left by then, he returned and so did I along with
him till he entered upon Zainab and behold, they were still
sitting and had not gone. So the Prophet again went away and I
went away along with him. When we reached the threshold of
`Aisha's dwelling place, he thought that they had left, and so
he returned and I too, returned along with him and found those
people had left. Then the Prophet drew a curtain between me
and him, and the Verses of Al−Hijab were revealed.