It was narrated that Ibn 'Abbas said:
"One of the wives of the Prophet took a bath from a large vessel, then the Prophet came and had a bath or ablution, and she said: 'O Messenger of Allah, I was sexually impure.' He said: 'Water does not become impure.'"

حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا أَبُو الأَحْوَصِ، عَنْ سِمَاكِ بْنِ حَرْبٍ، عَنْ عِكْرِمَةَ، عَنِ ابْنِ عَبَّاسٍ، قَالَ اغْتَسَلَ بَعْضُ أَزْوَاجِ النَّبِيِّ ـ ﷺ ـ فِي جَفْنَةٍ فَجَاءَ النَّبِيُّ ـ ﷺ ـ لِيَغْتَسِلَ أَوْ يَتَوَضَّأَ فَقَالَتْ يَا رَسُولَ اللَّهِ إِنِّي كُنْتُ جُنُبًا . فَقَالَ " الْمَاءُ لاَ يُجْنِبُ " .