Sa'id bin al-Musayyib and Sulayman bin Yasar (may Allah have mercy on them both) said: The Sunnah regarding these two verses, in which Allah, the Lord of Might, mentioned a man's ill-conduct towards his wife and his turning away from her, "And if a woman fears from her husband ill-conduct or desertion" [Surah al-Nisa: 128], is this: when a man treats his wife badly or prefers another over her, it is a duty upon him to give her the choice that either he divorces her or she stays with him, even though he prefers another over her in his own person and wealth. If the woman wishes to stay with him and does not want divorce, there is no harm on the man in preferring another over her. If the man does not divorce her but agrees to give the woman as much wealth as she wishes, and she wishes to stay with him despite the preference in wealth and turns, the settlement between them is valid. In this way Sa'id bin al-Musayyib and Sulayman bin Yasar (may Allah have mercy on them both) mentioned the settlement: "There is no blame on them if they make terms of settlement between them, and settlement is best." [Surah al-Nisa: 128]. Sayyiduna Rafi' bin Khadij (may Allah be pleased with him) had a wife; when she grew old, he married a young girl. The old woman demanded a divorce, so Rafi' bin Khadij (may Allah be pleased with him) divorced her. Then he kept her waiting, and when she was close to becoming free (from her waiting period), he took her back. Then Rafi' (may Allah be pleased with him) gave the young girl preference over her, so she again demanded a divorce, and Rafi' (may Allah be pleased with him) gave her a second divorce as well. Then he kept her waiting, and when she was close to becoming free, he again took her back. Then Rafi' (may Allah be pleased with him) gave preference to the young girl, and the old woman again demanded a divorce. Rafi' (may Allah be pleased with him) said: Now this is the last chance. If you wish, I will divorce you; if you wish to remain despite this preference, that is fine; otherwise I will separate from you. So the old woman chose to remain despite the preference. So he kept her; that was the settlement between them. And Rafi' (may Allah be pleased with him) did not consider that preference a sin, since she had agreed to stay.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب القسم والنشوز / 14731