Ask for permission before entering someone else's home.

This hadith is about the importance of asking permission before entering someone else's home. It is narrated by Ribi, who heard it from a man of Banu Amir. The man asked for permission to enter the Prophet's house and was granted it. This shows that we should always ask for permission before entering someone else's home as a sign of respect and politeness. We should also be respectful when we are given permission, as in this case where the man said "Peace be upon you". Respectful behavior is an important part of Islamic teachings and this hadith serves as an example for us all.