Sura al-Baqara 2:232

وَإِذَا طَلَّقْتُمُ ٱلنِّسَآءَ فَبَلَغْنَ أَجَلَهُنَّ فَلَا تَعْضُلُوهُنَّ أَن يَنكِحْنَ أَزْوَٰجَهُنَّ إِذَا تَرَٰضَوْا۟ بَيْنَهُم بِٱلْمَعْرُوفِ ذَٰلِكَ يُوعَظُ بِهِۦ مَن كَانَ مِنكُمْ يُؤْمِنُ بِٱللَّـهِ وَٱلْيَوْمِ ٱلْأَخِرِ ذَٰلِكُمْ أَزْكَىٰ لَكُمْ وَأَطْهَرُ وَٱللَّـهُ يَعْلَمُ وَأَنتُمْ لَا تَعْلَمُونَ

wa-idhā ṭallaqtumu l-nisāʾa fa-balaghna ajalahunna fa-lā taʿḍulūhunna an yankiḥna azwājahunna idhā tarāḍaw baynahum bil-maʿrūfi dhālika yūʿaẓu bihi man kāna minkum yuʾminū billāhi wa-l-yawmi l-akhiri dhālikum azka la-kum wa-aṭharu wallāhu yaʿlamu wa-antum lā taʿlamūna

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.