Ibn Mas'ud reported that a person came to Allah's Messenger (ﷺ) and told him that he had kissed a woman or touched her with his hand or did something like this. He inquired of him about its expiation. It was (on this occasion) that Allah, the Exalted and Glorious, revealed this verse (as mentioned above).
Reference: Sahih Muslim 2763 b In-book : Book 50, Hadith 48 USC-MSA web (English) : Book 37, Hadith 6656 (deprecated)
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