If any men among you divorce their wives by Zihar (calling them mothers), they cannot be their mothers: None can be their mothers except those who gave them birth. And in fact they use words (both) iniquitous and false: but truly Allah is one that blots out (sins), and forgives (again and again).
Prohibited to you (For marriage) are:- Your mothers, daughters, sisters; father's sisters, Mother's sisters; brother's daughters, sister's daughters; foster-mothers (Who gave you suck), foster-sisters; your wives' mothers; your step-daughters under your guardianship, born of your wives to whom ye have gone in,- no prohibition if ye have not gone in;- (Those who have been) wives of your sons proceeding from your loins; and two sisters in wedlock at one and the same time, except for what is past; for Allah is Oft-forgiving, Most Merciful;-
So if a husband divorces his wife (irrevocably), He cannot, after that, re-marry her until after she has married another husband and He has divorced her. In that case there is no blame on either of them if they re-unite, provided they feel that they can keep the limits ordained by Allah. Such are the limits ordained by Allah, which He makes plain to those who understand.
O ye who believe! Truly, among your wives and your children are (some that are) enemies to yourselves: so beware of them! But if ye forgive and overlook, and cover up (their faults), verily Allah is Oft-Forgiving, Most Merciful.
And if ye divorce them before consummation, but after the fixation of a dower for them, then the half of the dower (Is due to them), unless they remit it or (the man's half) is remitted by him in whose hands is the marriage tie; and the remission (of the man's half) is the nearest to righteousness. And do not forget Liberality between yourselves. For Allah sees well all that ye do.