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Surah 2. Al-Baqara
Ayah 231
231 وَإِذَا طَلَّقْتُمُ ٱلنِّسَآءَ فَبَلَغْنَ أَجَلَهُنَّ فَأَمْسِكُوهُنَّ بِمَعْرُوفٍ أَوْ سَرِّحُوهُنَّ بِمَعْرُوفٍ ۚ وَلَا تُمْسِكُوهُنَّ ضِرَارًا لِّتَعْتَدُوا۟ ۚ وَمَن يَفْعَلْ ذَٰلِكَ فَقَدْ ظَلَمَ نَفْسَهُۥ ۚ وَلَا تَتَّخِذُوٓا۟ ءَايَـٰتِ ٱللَّهِ هُزُوًا ۚ وَٱذْكُرُوا۟ نِعْمَتَ ٱللَّهِ عَلَيْكُمْ وَمَآ أَنزَلَ عَلَيْكُم مِّنَ ٱلْكِتَـٰبِ وَٱلْحِكْمَةِ يَعِظُكُم بِهِۦ ۚ وَٱتَّقُوا۟ ٱللَّهَ وَٱعْلَمُوٓا۟ أَنَّ ٱللَّهَ بِكُلِّ شَىْءٍ عَلِيمٌ
231. And when you have divorced women and they have fulfilled the term of their prescribed period, either take them back on a reasonable basis or set them free on a reasonable basis. But do not take them back to hurt them, and whoever does that, then he has wronged himself. And treat not the verses (Laws) of Allah in jest, but remember Allah's favors on you (i.e., Islam), and that which He has sent down to you of the Book (i.e., the Qur'an) and Al-Hikmah (the Prophet's Sunnah ـ legal ways ـ Islamic jurisprudence) whereby He instructs you. And fear Allah, and know that Allah is All-Aware of everything).
This is a command from Allah to men that when one of them divorces his wife with a reversible divorce, he should treat her kindly. So when her term of `Iddah (waiting period) nears its end, he either takes her back in a way that is better, including having witnesses that he has taken her back, and he lives with her with kindness. Or, he should release her after her `Iddah finishes and then kindly asks her to depart from his house, without disputing, fighting with her or using foul words. Allah then said:
(But do not take them back to hurt them,)
Ibn `Abbas, Mujahid, Masruq, Al-Hasan, Qatadah, Ad-Dahhak, Ar-Rabi` and Muqatil bin Hayyan said that a man used to divorce his wife, and when her `Iddah came near its end, he would take her back to harm her and to stop her from marrying someone else. He then divorced her and she would begin her `Iddah and when her `Iddah term neared its end, he would take her back again, so that the term of `Iddah would be prolonged for her. After that, Allah prohibited this practice. Allah has also threatened those who indulge in such practices, when He said;
(...and whoever does that, then he has wronged himself.) meaning, by defying Allah's commandments. Allah then said:
(And treat not the verses (Laws) of Allah in a jest,)
Ibn Jarir said that Abu Musa (Al-Ash`ari) narrated that Allah's Messenger once became angry at the Ash`ari tribe. Abu Musa went to him and said, "O Messenger of Allah! Are you angry with the Ash`ariyyin'' The Prophet said:
(One of you says, `I divorced her' -then says- `I took her back!' This is not the appropriate way Muslims conduct divorce. Divorce the woman when she has fulfilled the term of the prescribed period.)
Masruq said that the Ayah refers to the man who harms his wife by divorcing her and then taking her back, so that the `Iddah term is prolonged for her. Al-Hasan, Qatadah, `Ata' Al-Khurasani, Ar-Rabi` and Muqatil bin Hayyan said, "He is the man who divorces his wife and says, `I was joking.' Or he frees a servant or gets married and says, `I was only joking.' Allah revealed:
(And treat not the verses (Laws) of Allah in a jest,)
Then such men were made to bear the consequences of their actions.
Allah then said:
(. ..but remember Allah's favors on you,) meaning, by His sending His Messenger with the right guidance and clear signs to you:
(...and that which He has sent down to you of the Book (i.e., the Qur'an) and Al-Hikmah) meaning the Sunnah,
(...whereby He instructs you.) meaning, commands you, forbids you and threatens you for transgressing His prohibitions. Allah said:
(And fear Allah) meaning, concerning what you perform and what you avoid,
(and know that Allah is All-Aware of everything.) none of your secret or public affairs ever escapes His knowledge, and He will treat you accordingly.