Sunan an-Nasai 19607
In-book no 4871أَخْبَرَنَا مُحَمَّدُ بْنُ مَنْصُورٍ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " لَوْ أَنَّ امْرَأً اطَّلَعَ عَلَيْكَ بِغَيْرِ إِذْنٍ فَخَذَفْتَهُ فَفَقَأْتَ عَيْنَهُ مَا كَانَ عَلَيْكَ حَرَجٌ " . وَقَالَ مَرَّةً أُخْرَى " جُنَاحٌ " .
It was narrated from Abu Hurairah that the Prophet said: "If a person were to look at you without permission and you were to throw a stone at him and put out his eye, there would be no blame on you."