Narrated Aa’isha (radiyallaahu-anhaa): The Prophet (sallal-laahu-alayhi-wasallam) and I used to take a bath from a single pot of water and our hands used to go in the pot after each other in turn. [Bukhari Number 261]

Al-Haafidh Ibn Hajr (rahimahullaah) said:

Ad-daawoodiy (used this) as evidence regarding the permissibility for a man to look at the private parts of his wife and vice versa. This is supported by what Ibn Hibbaan narrated from Sulaymaan Ibn Moosaa that indeed he was asked regarding a man who looks at the private parts of his wife, so he (Sulaymaan) said: I asked Ataa, who said: ‘’I asked Aa’isha, so he mentioned this hadeeth and it is a determined text in this subject matter”. [Fat-hul Baari 1/364]