Hazrat Ash'ath narrates from a man that a person sat with Hasan, so he said to him: "You have sat with us at the time of our departure. Do we have your permission to leave?"

Hazrat Imran narrates that Hazrat Abu Majliz said: When a person deliberately sits with you, do not get up before seeking his permission.

The aforementioned statement from Ibrahim is narrated with the same chain of transmission.

Hazrat Anas bin Malik (may Allah be pleased with him) narrates that no person ever sat with the Messenger of Allah (peace and blessings be upon him) without the Prophet standing up when that person stood up.

Ibn Aun narrates that Muhammad did not see any harm in a person standing up without permission when someone was sitting with another person.

Hazrat Musa bin Nafi says that I was sitting with Hazrat Saeed bin Jubair. When he intended to get up, he said: You people are sitting with me, do I have your permission?

Hazrat Rabi'i narrates that a person from Banu Amir told me that he sought permission from the Prophet Muhammad (peace and blessings be upon him) while the Prophet (peace and blessings be upon him) was in the house. That person said: "May I come in?" The Prophet (peace and blessings be upon him) said to his servant: "Go to him and teach him the manner of seeking permission. Tell him to say: 'Assalamu Alaikum, may I come in?'" The man heard this and said: "Assalamu Alaikum, may I come in?" So the Prophet (peace and blessings be upon him) granted him permission to enter, and he entered.

Hazrat Amir bin Abdullah bin Zubair narrates that Hazrat Raihana stated: My family sent me to Hazrat Umar, so I entered his presence without permission. He taught me the manner of seeking permission and said: Go outside, then offer salam, and when your salam is answered, then seek permission to enter.

Hazrat Abu Ayyub Ansari narrates that we asked: O Messenger of Allah (peace and blessings be upon him)! This is how to greet, but how should permission be sought? The Prophet (peace and blessings be upon him) said: A person should say Subhan Allah, Allahu Akbar, Alhamdulillah, or clear his throat, and thus give permission to the people of the house.

Hazrat Zaid bin Aslam narrates that my father sent me to Hazrat Ibn Umar (may Allah be pleased with them). So I said to him: "Shall I come in?" He replied: "Do not say it like this, rather say: 'Assalamu Alaikum.' When it is said to you, 'Wa Alaikum Assalam,' then you may enter."