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وَٱلْمُطَلَّقَٰتُ يَتَرَبَّصْنَ بِأَنفُسِهِنَّ ثَلَٰثَةَ قُرُوٓءٍۢ ۚ وَلَا يَحِلُّ لَهُنَّ أَن يَكْتُمْنَ مَا خَلَقَ ٱللَّهُ فِىٓ أَرْحَامِهِنَّ إِن كُنَّ يُؤْمِنَّ بِٱللَّهِ وَٱلْيَوْمِ ٱلْءَاخِرِ ۚ وَبُعُولَتُهُنَّ أَحَقُّ بِرَدِّهِنَّ فِى ذَٰلِكَ إِنْ أَرَادُوٓا۟ إِصْلَٰحًۭا ۚ وَلَهُنَّ مِثْلُ ٱلَّذِى عَلَيْهِنَّ بِٱلْمَعْرُوفِ ۚ وَلِلرِّجَالِ عَلَيْهِنَّ دَرَجَةٌۭ ۗ وَٱللَّهُ عَزِيزٌ حَكِيمٌ
Divorced women remain in waiting for three periods, and it is not lawful for them to conceal what Allah has created in their wombs if they believe in Allah and the Last Day. And their husbands have more right to take them back in this [period] if they want reconciliation. And due to the wives is similar to what is expected of them, according to what is reasonable. But the men have a degree over them [in responsibility and authority]. And Allah is Exalted in Might and Wise.
Translation · Saheeh International
Tafsir
Ibn Kathīr (abridged)
The `Iddah (Waiting Period) of the Divorced Woman
This Ayah contains a command from Allah that the divorced woman, whose marriage was consummated and who still has menstruation periods, should wait for three (menstrual) periods (Quru') after the divorce and then remarry if she wishes.
The Meaning of Al-Quru
Ibn Jarir related that `Alqamah said: We were with `Umar bin Al-Khattab when a woman came and said, "My husband divorced me one or two periods ago. He then came back to me while I had prepared my water for taking a bath, took off my clothes and closed my door." `Umar asked `Abdullah bin Mas`ud, "What do you think" He said, "I think that she is still his wife, as long as she is not allowed to resume praying (i.e., until the third period ends before he takes her back)." `Umar said, "This is my opinion too." This is also the opinion of Abu Bakr As-Siddiq, `Umar, `Uthman, `Ali, Abu Ad-Darda', `Ubadah bin As-Samit, Anas bin Malik, Ibn Mas`ud, Mu`adh, Ubayy bin Ka`b, Abu Musa Al-Ash`ari and Ibn `Abbas. Furthermore, this is the opinion of Sa`id bin Musayyib, `Alqamah, Aswad, Ibrahim, Mujahid, `Ata', Tawus, Sa`id bin Jubayr, `Ikrimah, Muhammad bin Sirin, Al-Hasan, Qatadah, Ash-Sha`bi, Ar-Rabi`, Muqatil bin Hayyan, As-Suddi, Makhul, Ad-Dahhak and `Ata' Al-Khurasani. They all stated that the Quru' is the menstruation period. What testifies to this is the Hadith that Abu Dawud and An-Nasa'i reported that Fatimah bint Abu Hubaiysh said that Allah's Messenger ﷺ said to her:
«دَعِي الصَّلاَةَ أَيَّامَ أَقْرَائِك»
(Do not pray during your Aqra' (pl. for Quru', the menstruation period).)