Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates: One of the noble wives of the Prophet (peace and blessings be upon him) performed ghusl (ritual bath) in a tub (of water), then the Prophet (peace and blessings be upon him) came and began to perform wudu (ablution) or perhaps ghusl with the leftover water. The lady said: O Messenger of Allah! I was in a state of janabah (major ritual impurity). The Prophet (peace and blessings be upon him) said: Nothing makes water impure.
Hadith Referenceصحیح ابن حبان / كتاب الطهارة / 1269
Hadith Gradingفضيلة الشيخ الإمام محمد ناصر الدين الألبانيصحيح - «صحيح أبي داود» (61).فضيلة الشيخ العلّامة شُعيب الأرناؤوطتقدم الحديث في (1241) و (1242)، فانظر تخريجه هناك.