(3) CHAPTER. The Statement of Allah: (O you believe!) Enter not the Prophet's houses unless permission is given to you...” (V.33:53)
Narrated Abu Musa: The Prophet entered a garden and told me to guard its gate. Then a man came and asked permission to enter. The Prophet, said, Permit him and give him the good news that he will enter Paradise. Behold! It was Abu Bakr. Then `Umar came, and the Prophet said, Admit him and give him the good news that he will enter Paradise. Then `Uthman came and the Prophet said, Admit him and give him the good news that he will enter Paradise.
Narrated `Umar: I came and behold, Allah's Apostle was staying on a Mashroba (attic room) and a black slave of Allah's Apostle was at the top if its stairs. I said to him, (Tell the Prophet) that here is `Umar bin Al- Khattab (asking for permission to enter). Then he admitted me.