Al-Baqarah - 2:231

وَإِذَا طَلَّقْتُمُ النَّسَاء فَبَلَغْنَ أَجَلَهُنَّ فَأَمْسِكُوهُنَّ بِمَعْرُوفٍ أَوْ سَرِّحُوهُنَّ بِمَعْرُوفٍ وَلاَ تُمْسِكُوهُنَّ ضِرَارًا لَّتَعْتَدُواْ وَمَن يَفْعَلْ ذَلِكَ فَقَدْ ظَلَمَ نَفْسَهُ وَلاَ تَتَّخِذُوَاْ آيَاتِ اللّهِ هُزُوًا وَاذْكُرُواْ نِعْمَتَ اللّهِ عَلَيْكُمْ وَمَا أَنزَلَ عَلَيْكُمْ مِّنَ الْكِتَابِ وَالْحِكْمَةِ يَعِظُكُم بِهِ وَاتَّقُواْ اللّهَ وَاعْلَمُواْ أَنَّ اللّهَ بِكُلِّ شَيْءٍ عَلِيمٌ
[2:231]
And when you divorce women and they reach their prescribed time, then either retain them in good fellowship or set them free with liberality, and do not retain them for injury, so that you exceed the limits, and whoever does this, he indeed is unjust to his own soul; and do not take Allah's communications for a mockery, and remember the favor of Allah upon you, and that which He has revealed to you of the Book and the Wisdom, admonishing you thereby; and be careful (of your duty to) Allah, and know that Allah is the Knower of all things.
When ye divorce women, and they fulfil the term of their ('Iddat), either take them back on equitable terms or set them free on equitable terms; but do not take them back to injure them, (or) to take undue advantage; if any one does that; He wrongs his own soul. Do not treat Allah's Signs as a jest, but solemnly rehearse Allah's favours on you, and the fact that He sent down to you the Book and Wisdom, for your instruction. And fear Allah, and know that Allah is well acquainted with all things.
When ye have divorced women, and they have reached their term, then retain them in kindness or release them in kindness. Retain them not to their hurt so that ye transgress (the limits). He who doeth that hath wronged his soul. Make not the revelations of Allah a laughing-stock (by your behaviour), but remember Allah's grace upon you and that which He hath revealed unto you of the Scripture and of wisdom, whereby He doth exhort you. Observe your duty to Allah and know that Allah is Aware of all things.