The Messenger of Allah said: "No woman should look at the nakedness of another woman, and no man should look at the nakedness of another man."  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ لاَ تَنْظُرِ الْمَرْأَةُ إِلَى عَوْرَةِ الْمَرْأَةِ وَلاَ يَنْظُرِ الرَّجُلُ إِلَى عَوْرَةِ الرَّجُلِ  

'Aishah said: "I never looked at (or I never saw) the private part of the Messenger of Allah." (Da'if)(One of the narrators) Abu Bakr (Ibn Abu Shaibah) said: "Abu Nu'aim would say: '(From) a freed female slave of 'Aishah.'"  

مَا نَظَرْتُ أَوْ مَا رَأَيْتُ فَرْجَ رَسُولِ اللَّهِ ﷺ قَطُّ قَالَ أَبُو بَكْرٍ كَانَ أَبُو نُعَيْمٍ يَقُولُ عَنْ مَوْلاَةٍ لِعَائِشَةَ