Narrated Anas bin Malik:
When Allah's Messenger (ﷺ) married Zainab bint Jahsh, he invited the people who took their meals and then remained sitting and talking. The Prophet (ﷺ) pretended to be ready to get up, but the people did not get up. When he noticed that, he got up, and when he had got up, some of those people got up along with him and there remained three (who kept on sitting). Then the Prophet (ﷺ) came back and found those people still sitting. Later on those people got up and went away. So I went to the Prophet (ﷺ) and informed him that they had left. The Prophet (ﷺ) came, and entered (his house). I wanted to enter(along with him) but he dropped a curtain between me and him. Allah then revealed: 'O you who believe! Do not enter the Prophet's Houses until leave is given... (to His statement)... Verily! That shall be an enormity, in Allah's sight.' (33.53)