Sura al-Nūr 24:27

يَٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوا۟ لَا تَدْخُلُوا۟ بُيُوتًا غَيْرَ بُيُوتِكُمْ حَتَّىٰ تَسْتَأْنِسُوا۟ وَتُسَلِّمُوا۟ عَلَىٰٓ أَهْلِهَا ذَٰلِكُمْ خَيْرٌ لَّكُمْ لَعَلَّكُمْ تَذَكَّرُونَ

yā-ayyuhā lladhīna āmanū lā tadkhulū buyūtan ghayra buyūtikum ḥattā tastaʾnisū wa-tusallimū ʿala ahlihā dhālikum khayrun la-kum la-ʿallakum tadhakkarūna

O ye who believe! enter not houses other than your own, until ye have asked permission and saluted those in them: that is best for you, in order that ye may heed (what is seemly).