Al-Hasan (al-Basri) (may Allah have mercy on him) relates concerning the saying of Allah, the Mighty and Majestic: "Then do not prevent them from marrying their (former) husbands when they agree between themselves in a fair manner" [Al-Baqarah: 232], that Ma'qil bin Yasar (may Allah be pleased with him) told him that this verse was revealed concerning him. He said: I married a sister of mine to a man, then he divorced her. Then he left her until, when her waiting period ('iddah) was over, he sent a proposal of marriage for her again. I said: I married you (to her), spread a bed for you and honoured you, then you divorced her, and now you have come proposing for her? No, by Allah! She will never return to you. Yet the man was not a bad man, and the woman also wanted to return to him. So Allah Almighty revealed this verse. I said: Now I will do it, O Messenger of Allah! So I married her to him.
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 17601