Allah Almighty says: {O you who believe, do not enter houses other than your own houses until you ascertain welcome and greet their inhabitants} [Surat an-Nūr: 27] He also says: {And when the children among you reach puberty, let them ask permission [at all times] as those before them have done} [Surat an-Nūr: 59]
1) When a child reaches puberty, he should not enter the house without permission, just like adults.
2) Children below the age of puberty should be asked to seek permission at the three private times.
3) The three private times at which people change to lighter clothes for rest are outlined in the Qur’an: {Before the dawn prayer and when you put aside your clothing [for rest] at noon and after the ‘Ishā’ prayer} [Surat an-Nūr: 58]
870/1 - Abu Mūsa al-Ash‘ari (may Allah be pleased with him) reported that the Prophet (may Allah’s peace and blessings be upon him) said: “Permission should be sought three times, and if it is not given, then turn back.” [Narrated by Al-Bukhāri and Muslim]
1) The Islamic etiquette is that a person seeks permission up to three times and not knock on the door after that.
2) It shows the perfect guidance of Islam which takes people’s conditions into consideration and teaches the believers their rights upon one another.
871/2 - Sahl ibn Sa‘d (may Allah be pleased with him) reported that the Prophet (may Allah’s peace and blessings be upon him) said: “Seeking permission is enjoined only so as to prevent looking.” [Narrated by Al-Bukhāri and Muslim]
1) The Shariah is keen on protecting the privacy of homes; that is why it prescribed seeking permission before entering a home in order to protect its privacy against looking.
2) It is prohibited to look inside homes before seeking permission.
872/3 - Rib‘i ibn Hirāsh reported: A man from Banu ‘Āmir related to us that he asked the Prophet (may Allah’s peace and blessings be upon him) for permission to enter when he was in his house, saying: “Do I come in?” The Prophet said to his servant: “Go out to this (man) and teach him how to ask permission to enter the house, and say to him: ‘Say: Peace be upon you. May I come in?’” The man heard it and said: “Peace be upon you. May I come in?” The Prophet (may Allah’s peace and blessings be upon him) gave him permission and he entered.
[Narrated by Abu Dāwūd, with an authentic Isnād]
873/4 - Kildah ibn al-Hanbal (may Allah be pleased with him) reported: I went to the Prophet (may Allah’s peace and blessings be upon him) and entered his place without saying the greeting of peace. Thereupon, he said: “Go back and say: Peace be upon you. May I come in?” [Narrated by Abu Dāwūd and Al-Tirmidhi, who classified it as Hasan (sound)]
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1) One of the etiquettes of seeking permission is to give the greeting of peace and wait until permission to enter is granted.
2) The Prophet (may Allah’s peace and blessings be upon him) taught his Ummah the proper etiquettes, and he did so using both words and deeds.