If I were to know that you had been peeping through the door, I would have thrust that into your eyes, and Messenger of Allah ﷺ said: Permission is needed as a protection against glance.  

أَخْبَرَهُ أَنَّ رَجُلاً اطَّلَعَ فِي جُحْرٍ فِي بَابِ رَسُولِ اللَّهِ ﷺ وَمَعَ رَسُولِ اللَّهِ ﷺ مِدْرًى يَحُكُّ بِهِ رَأْسَهُ فَلَمَّا رَآهُ رَسُولُ اللَّهِ ﷺ قَالَ لَوْ أَعْلَمُ أَنَّكَ تَنْظُرُنِي لَطَعَنْتُ بِهِ فِي عَيْنِكَ وَقَالَ رَسُولُ اللَّهِ ﷺ إِنَّمَا جُعِلَ الإِذْنُ مِنْ أَجْلِ الْبَصَرِ  

If I were to know that you had been peeping. I would have thrust it in your eyes. Allah has prescribed seeking permission because of protection against glance.  

أَنَّأَخْبَرَهُ أَنَّ رَجُلاً اطَّلَعَ مِنْ جُحْرٍ فِي بَابِ رَسُولِ اللَّهِ ﷺ وَمَعَ رَسُولِ اللَّهِ ﷺ مِدْرًى يُرَجِّلُ بِهِ رَأْسَهُ فَقَالَ لَهُ رَسُولُ اللَّهِ ﷺ لَوْ أَعْلَمُ أَنَّكَ تَنْظُرُ طَعَنْتُ بِهِ فِي عَيْنِكَ إِنَّمَا جَعَلَ اللَّهُ الإِذْنَ مِنْ أَجْلِ الْبَصَرِ  

This hadith has been transmitted on the authority of Sahl b. Sa'd as-Sa'idi with a slight variation of wording.  

عَنِ النَّبِيِّ ﷺ نَحْوَ حَدِيثِ اللَّيْثِ وَيُونُسَ  

I perceived as if Messenger of Allah ﷺ was going to pierce (his eyes).  

أَنَّ رَجُلاً اطَّلَعَ مِنْ بَعْضِ حُجَرِ النَّبِيِّ ﷺ فَقَامَ إِلَيْهِ بِمِشْقَصٍ أَوْ مَشَاقِصَ فَكَأَنِّي أَنْظُرُ إِلَى رَسُولِ اللَّهِ ﷺ يَخْتِلُهُ لِيَطْعُنَهُ  

He who peeped into the house of people without their consent, it is permissible for them to put out his eyes.  

عَنِ النَّبِيِّ ﷺ قَالَ مَنِ اطَّلَعَ فِي بَيْتِ قَوْمٍ بِغَيْرِ إِذْنِهِمْ فَقَدْ حَلَّ لَهُمْ أَنْ يَفْقَئُوا عَيْنَهُ  

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.  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ لَوْ أَنَّ رَجُلاً اطَّلَعَ عَلَيْكَ بِغَيْرِ إِذْنٍ فَخَذَفْتَهُ بِحَصَاةٍ فَفَقَأْتَ عَيْنَهُ مَا كَانَ عَلَيْكَ مِنْ جُنَاحٍ