Al-Baqarah 2:229 الطلاق مرتان فامساك بمعروف او تسريح باحسان ولا يحل لكم ان تاخذوا مما اتيتموهن شييا الا ان يخافا الا يقيما حدود الله فان خفتم الا يقيما حدود الله فلا جناح عليهما فيما افتدت به تلك حدود الله فلا تعتدوها ومن يتعد حدود الله فاولايك هم الظالمون ٢٢٩

Divorce must be pronounced twice and then (a woman) must be retained in honour or released in kindness. And it is not lawful for you that ye take from women aught of that which ye have given them; except (in the case) when both fear that they may not be able to keep within the limits (imposed by) Allah. And if ye fear that they may not be able to keep the limits of Allah, in that case it is no sin for either of them if the woman ransom herself. These are the limits (imposed by) Allah. Transgress them not. For whoso transgresseth Allah's limits: such are wrong-doers.