From Sahih Bukhari (Hadith 4690):
Narrated Az-Zuhri:`Urwa bin Az-Zubair, Sa`id bin Al-Musaiyab, 'Al-Qama bin Waqqas and 'Ubaidullah bin `Abdullah related the narration of `Aisha, the wife of the Prophet, when the slanderers had said about her what they had said and Allah later declared her innocence. Each of them related a part of the narration (wherein) the Prophet (ﷺ) said (to `Aisha). "If you are innocent, then Allah will declare your innocence: but if you have committed a sin, then ask for Allah's Forgiveness and repent to Him." `Aisha said, "By Allah, I find no example for my case except that of Joseph's father (when he said), 'So (for me) patience is most fitting.' " Then Allah revealed the ten Verses:-- "Verily those who spread the slander are a gang amongst you
Reference: Bukhari 4690