[Verse 232] "And when you have divorced women and they have fulfilled their term," meaning: the completion of the waiting period (idda), "do not prevent them from remarrying their husbands," meaning: do not restrain them. "That is more virtuous for you and more pure," meaning: for the heart of the man and the heart of the woman.
Yahya narrated from al-Mubarak ibn Fadalah, from al-Hasan: "That Ma'qil ibn Yasar gave his sister in marriage to a man, and the man divorced her once. When her waiting period had passed, he proposed to her, and she wanted to marry him. Ma'qil became angry and said: 'I gave her in marriage to him, and then he divorced her; she shall not return to him.' Then Allah revealed this verse up to His saying: 'And Allah knows, while you do not know,'" meaning: Allah knew his need for her and her need for him.