All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
It has been reported that angels do not enter if there is a woman who is without head covering. Khadeejah said: "I said O Prophet of Allaah! When the angel comes to you, inform me." He replied: "Yes, I will inform you, O Khadeejah." She said: "One day I was with him when the angel Jibreel came to him. So he said: "O Khadeejah, the angel who comes to me has arrived." So, I said to him: "Stand up and sit on my right thigh." So he came and sat on my right thigh. I asked him: "Can you see him? He replied: "Yes, I can." Then I asked him: "Come and sit on my left thigh." He sat on my left thigh. I then asked him: "Can you see him?" He again replied: "Yes, I can." I then asked him: "Come and sit in my lap? He sat on my lap. I asked: "Can you see him? He said: "Yes, I can." Thereupon Khadeejah said: So I was confused and threw my head covering, then I asked: "Can you see him? He replied: "No, I can't see him." I then said: "I swear by Allaah, this is none other than a noble angel. No, this is not a devil.'' Khadeejah said to Waraqah Ibn Nawfal this is indeed as the Prophet informed me about. He said: "You have indeed spoken the truth." [At-Tabaraani] However, the authenticity of the above wording depends on the authenticity of the narration. Nonetheless, Al-Haythami considered the chain of narrators of the above narration to be sound. Imaam At-Tabari and Ibn Katheer also mentioned the above story.
Allaah Knows best.