Qatadah said concerning this verse: "And had it not been for the favour of Allah upon you and His mercy, you would have been touched by a great punishment because of what you indulged in": This is about the affair of Sayyidah Aishah (may Allah be pleased with her) and what was said; the Companions of the Messenger of Allah (peace and blessings be upon him) were close to being destroyed by it.
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 19499