Quran 24:27 from Surah An-Noor on Divine Marvels.
يَٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُواْ لَا تَدۡخُلُواْ بُيُوتًا غَيۡرَ بُيُوتِكُمۡ حَتَّىٰ تَسۡتَأۡنِسُواْ وَتُسَلِّمُواْ عَلَىٰٓ أَهۡلِهَاۚ ذَٰلِكُمۡ خَيۡرٞ لَّكُمۡ لَعَلَّكُمۡ تَذَكَّرُونَ
English translation: O you who believe! (Do) not enter houses other (than) your houses until you have asked permission and you have greeted [on] its inhabitants That (is) best for you so that you may pay heed
Transliteration: yaayyuha alladhina amanu la tadkhulu buyutan ghayra buyutikum hatta tastanisu watusallimu ala ahliha dhalikum khayrun lakum la'allakum tadhakkaruna