Al-Baqarah - 2:232

وَإِذَا طَلَّقْتُمُ النِّسَاء فَبَلَغْنَ أَجَلَهُنَّ فَلاَ تَعْضُلُوهُنَّ أَن يَنكِحْنَ أَزْوَاجَهُنَّ إِذَا تَرَاضَوْاْ بَيْنَهُم بِالْمَعْرُوفِ ذَلِكَ يُوعَظُ بِهِ مَن كَانَ مِنكُمْ يُؤْمِنُ بِاللّهِ وَالْيَوْمِ الآخِرِ ذَلِكُمْ أَزْكَى لَكُمْ وَأَطْهَرُ وَاللّهُ يَعْلَمُ وَأَنتُمْ لاَ تَعْلَمُونَ
[2:232]
And when you have divorced women and they have ended-- their term (of waiting), then do not prevent them from marrying their husbands when they agree among themselves in a lawful manner; with this is admonished he among you who believes in Allah and the last day, this is more profitable and purer for you; and Allah knows while you do not know.
When ye divorce women, and they fulfil the term of their ('Iddat), do not prevent them from marrying their (former) husbands, if they mutually agree on equitable terms. This instruction is for all amongst you, who believe in Allah and the Last Day. That is (the course Making for) most virtue and purity amongst you and Allah knows, and ye know not.
And when ye have divorced women and they reach their term, place not difficulties in the way of their marrying their husbands if it is agreed between them in kindness. This is an admonition for him among you who believeth in Allah and the Last Day. That is more virtuous for you, and cleaner. Allah knoweth; ye know not.