Narrated Al-Hasan: The sister of Ma'qal bin Yasar was divorced by her husband who left her till she had fulfilled her term of 'Iddat (i.e. the period which should elapse before she can Remarry) and then he wanted to remarry her but Maqal refused, so this Verse was revealed:-- "Do not prevent them from marrying their (former) husbands." (2.232)

Narrated Al-Hasan: concerning the Verse: 'Do not prevent them' (2.232) Ma'qil bin Yasar told me that it was revealed in his connection. He said, "I married my sister to a man and he divorced her, and when her days of 'Idda (three menstrual periods) were over, the man came again and asked for her hand, but I said to him, 'I married her to you and made her your bed (your wife) and favored you with her, but you divorced her. Now you come to ask for her hand again? No, by Allah, she will never go back to you (again)!' That man was not a bad man and his wife wanted to go back to him. So Allah revealed this Verse: 'Do not prevent them.' (2.232) So I said, 'Now I will do it (let her go back to him), O Allah's Apostle."So he married her to him again.

Narrated Al-Hasan: Ma'qil gave his sister in marriage and later her husband divorced her once.

Narrated Al-Hasan: The sister of Ma'qil bin Yasar was married to a man and then that man divorced her and remained away from her till her period of the 'Iddah expired. Then he demanded for her hand in marriage, but Ma'qil got angry out of pride and haughtiness and said, "He kept away from her when he could still retain her, and now he demands her hand again?" So Ma'qil disagreed to remarry her to him. Then Allah revealed: 'When you have divorced women and they have fulfilled the term of their prescribed period, do not prevent them from marrying their (former) husbands.' (2.232) So the Prophet sent for Ma'qil and recited to him (Allah's order) and consequently Ma'qil gave up his pride and haughtiness and yielded to Allah's order.