وَإِذَا طَلَّقْتُمُ النِّسَاءَ فَبَلَغْنَ أَجَلَهُنَّ فَلَا تَعْضُلُوهُنَّ أَن يَنكِحْنَ أَزْوَاجَهُنَّ إِذَا تَرَاضَوْا بَيْنَهُم بِالْمَعْرُوفِ ۗ ذَٰلِكَ يُوعَظُ بِهِ مَن كَانَ مِنكُمْ يُؤْمِنُ بِاللَّهِ وَالْيَوْمِ الْآخِرِ ۗ ذَٰلِكُمْ أَزْكَىٰ لَكُمْ وَأَطْهَرُ ۗ وَاللَّهُ يَعْلَمُ وَأَنتُمْ لَا تَعْلَمُونَ
البقرة [232] And when you divorce women and they have fulfilled their term, do not prevent them from remarrying their [former] husbands if they agree among themselves on an acceptable basis. That is instructed to whoever of you believes in Allah and the Last Day. That is better for you and purer, and Allah knows and you know not.
Al-Baqarah ( The Cow ) [232]