Sayyiduna Ibn Abbas (may Allah be pleased with them both) said: "When you received it with your tongues from one another and said with your mouths that of which you had no knowledge" [Surah An-Nur: 15]; he said: Allah knew the opposite of it. "And you thought it insignificant, while in the sight of Allah it was tremendous" [Surah An-Nur: 15]; he said: meaning if you accuse the leader of the Mothers of the Believers and the wife of the Messenger of Allah (peace and blessings be upon him), and attribute to her what was not in her and what had never even crossed her heart, whereas I (Allah) created her pure and protected her from every evil.
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 19500