Surah Al-Ahzaab (33) — Ayah 53

53. O you who believe! Do not enter the houses of the Prophet [86] unless you are given permission, nor should you wait for a meal to be prepared [87]. But when you are invited, then enter; and when you have eaten, then leave, and do not linger, engaged in conversation [88]. This was troublesome for the Prophet, but he was shy to tell you; yet Allah is not shy of the truth. And when you ask his wives for anything [89], ask them from behind a screen. That is purer for your hearts and their hearts [90]. And it is not lawful for you to harm Allah’s Messenger [91], nor to ever marry his wives [92] after him. Surely, this is a grave offense in the sight of Allah.

[86]
Restriction on Entering Homes (Permission):

In this verse, several social etiquettes are being mentioned. In this same surah, earlier the wives of the Prophet were addressed and told that the real place for women is the home. They should not go out of the house without necessity, nor should women go out adorned and displaying their beauty like in the days of ignorance. And this command was limited only to going out or to the restriction of voice. Even now, people used to come and go freely in all homes, even in the houses of the Messenger of Allah ﷺ himself, and especially Sayyiduna Umar ؓ found it unpleasant that all kinds of people would enter the Prophet’s house without restriction. Thus, in accordance with his wish, divine revelation was sent down as is clear from the following hadith: Sayyiduna Anas bin Malik ؓ says that Sayyiduna Umar ؓ said to the Noble Prophet ﷺ: “O Messenger of Allah ﷺ! Good and bad people of all kinds come to you. Would it not be better if you commanded the Mothers of the Believers (your wives) to observe the veil?” At that time, Allah Almighty revealed the command of the veil. [بخاري۔ كتاب التفسير]
After this, the verses of Surah Nur were revealed, and according to verse 27, this command was enforced upon all Muslim households that no person should enter another’s house without permission.
[87]
Etiquette of Invitation to Food:

In this sentence, two further instructions are given. One is that if the master of the house himself invites you, especially for a meal, then you should go to his house, and his invitation itself is his permission. The second instruction is that you should come at the time you are invited, not before. It should not happen that you come early and keep looking at the cooking and serving utensils, waiting for when the food will be ready and when you will get to eat. This also becomes a cause of discomfort for the host.
[88] In this context, the fourth instruction is that when you have finished eating, do not just sit there and start talking about various matters and stories. Rather, when you have finished eating, you should leave, and not become a cause of waiting and discomfort for the host, because after the invitation, they also have many tasks to attend to.
[89]
The Verse of Hijab:

This is the verse which is called the Verse of Hijab. Hijab means to create such a barrier between two things with a cloth or something else that both things become hidden from each other. According to this verse, a curtain was hung outside the houses of all the wives of the Prophet. Then other Muslims also hung curtains in front of their homes, and this practice became a part of Islamic social conduct. Now, if anyone needed to ask the purified wives anything or needed something from them, he was commanded to ask from outside the curtain. Now, observe the reason for the revelation of this verse as narrated by Sayyiduna Anas ؓ:

The Three Persons Who Remained Seated After the Wedding Feast:

Sayyiduna Anas ؓ says that when you ﷺ married Zainab bint Jahsh and consummated the marriage, (for the wedding feast) meat and bread were prepared. I was sent to invite people. People would come, eat, and leave, then others would come, eat, and leave. I invited everyone until there was no one left whom I had not invited. You ﷺ said to me: “Alright, now remove the food.” (People left, but) three persons remained sitting and kept talking. You ﷺ got up and went towards the room of Sayyidah Aisha ؓ and said: “As-salamu ‘alaykum wa rahmatullahi wa barakatuh.” Sayyidah Aisha ؓ replied: “Wa ‘alayka as-salam wa rahmatullah! How did you find your wife? May Allah bless you ﷺ.” Then you ﷺ visited the rooms of all your wives and greeted them as you had greeted Sayyidah Aisha ؓ, and they replied in the same way. Then you ﷺ returned home, but those three men were still sitting and talking. You ﷺ were very modest by nature (so you did not say anything to them), so you went again to the room of Sayyidah Aisha ؓ. Then someone informed you ﷺ that those three men had now left. So you ﷺ returned, and as you stood at the threshold, one foot inside and one outside, you hung a curtain between me and yourself. At that moment, Allah Almighty revealed the verse of the veil. [بخاري۔ كتاب التفسير]
[90]
Prevention of Free Mixing Between Men and Women and the Command of Veil:

This is an effective measure to prevent free mixing between men and women and to curb indecency, that no non-mahram man should look at a strange woman, nor should any evil thought or temptation arise in anyone’s heart. In other words, to eradicate immodesty and indecency from society, the veil is a very necessary thing. Now, those people who, despite being Muslims, say that the real veil is the veil of the heart, because modesty and evil thoughts are related to the heart, and this outward veil is not necessary—such people are in fact mocking the commands of Allah.
[91]
That Which Causes Harm to the Messenger of Allah is Unlawful:

In terms of the context, this refers to those people who, after eating, would not even think of leaving. The Messenger of Allah ﷺ found this behavior very unpleasant and distressing, but due to his modesty and gentle nature, he could not tell them to leave. However, this command is general and its scope is very broad. It also includes the accusations that, in those days, the hypocrites along with the disbelievers were making against the Messenger of Allah ﷺ, as well as every matter which the Messenger of Allah ﷺ finds unpleasant; Muslims must avoid such things. For example, if someone accepts another’s word over the Messenger of Allah, or prefers someone else’s statement over the Sunnah of the Messenger, or abandons the Sunnah and promotes or spreads innovations, then these things cause distress to the Messenger of Allah ﷺ, and in all such matters, Muslims should be cautious.
[92] This is a grave sin in that the wives of the Prophet ﷺ are the mothers of the believers. And if anyone were to marry them, it would be as if he had married his own mother. Then, the respect which Allah has granted them would never be observed, and one would ruin his own hereafter.