The Book of Manners and Etiquette
38/9. Chapter:
The Prohibition Of Looking Into A House
Sahih Muslim
حَدَّثَنَا ابْنُ أَبِي عُمَرَ، حَدَّثَنَا سُفْيَانُ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " لَوْ أَنَّ رَجُلاً اطَّلَعَ عَلَيْكَ بِغَيْرِ إِذْنٍ فَخَذَفْتَهُ بِحَصَاةٍ فَفَقَأْتَ عَيْنَهُ مَا كَانَ عَلَيْكَ مِنْ جُنَاحٍ " .
Abu Huraira reported Allah's Messenger (ﷺ) as saying: If a person were to cast a glance in your (house) without permission, and you had in your hand a staff and you would have thrust that in his eyes, there is no harm for you.
Reference : Sahih Muslim 2158bIn-book reference : Book 38, Hadith 58USC-MSA web (English) reference : Book 25, Hadith 5371