"Narrated Anas bin Malik: that he was a boy of ten at the time when the Prophet emigrated to Medina. He added: I served Allah's Apostle for ten years (the rest of his life time) and I know more than the people about the occasion whereupon the order of Al-Hijab was revealed (to the Prophet). Ubai bin Ka'b used to ask me about it. It was revealed for the first time during the marriage of Allah's Apostle with Zainab bint Jahsh. In the morning, the Prophet was a bride-groom of her and he Invited the people, who took their meals and went away, but a group of them remained with Allah's Apostle and they prolonged their stay. Allah's Apostle got up and went out, and I too, went out along with him till he came to the lintel of 'Aisha's dwelling place. Allah's Apostle thought that those people had left by then, so he returned, and I too, returned with him till he entered upon Zainab and found that they were still sitting there and had not yet gone. The Prophet went out again, and so did I with him till he reached the lintel of 'Aisha's dwelling place, and then he thought that those people must have left by then, so he returned, and so did I with him, and found those people had gone. At that time the Divine Verse of Al-Hijab was revealed, and the Prophet set a screen between me and him (his family)."