Attalaqu marratani fa-imsakun bimaAAroofin aw tasreehun bi-ihsanin wala yahillu lakum an ta'khuthoo (surah Baqarah: 229)

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(2:229) Divorce may be pronounced twice; then either the wife be kept honourably or parted with gracefully. *250 And it is not lawful for you to take back anything out of what you have given them. *251 There is, however, an exception to this; if you fear that they might not be able to keep within the limits imposed by Allah, there is no harm if both agree mutually that the wife should obtain divorce by giving something as compensation to the husband. *252 These are the bounds set by Allah; therefore do not violate them, for those who violate the bounds of AIIah are the tansgressors.

Attalaaqu marrataani fa imsaakum bima`roofin aw tasreehum bi ihsaan; wa laa yahillu lakum an taakhuzoo mimmaaa aataitumoohunna shai`an illaaa ai yakhaafaaa alla yuqeemaa hudoodallahi fa in khiftum allaa yuqeemaa budoodal laahi falaa junaaha `Alaihimaa feemaf tadat bihee tilka hudoodul laahi falaa ta`tadoohaa; wa mai yata`adda hudoodal laahi fa ulaaa`ika humuzzaa limoon

*250). This little verse aims at the reform of a serious evil that was rampant in the social life in pre-Islamic Arabia. According to the customary law of Arabia, a person was entitled to pronounce any number of divorces upon his wife. As a result divorce was resorted to at the least provocation and annoyance. In addition, the husband often exercised his right to revoke the divorce he had pronounced with the result that the poor wife could neither live with him in happiness nor free herself to contract a fresh marriage with someone else. Here the Qur'an seeks to shut the door on this injustice. According to this verse, a man may pronounce revocable divorce upon his wife not more than twice. Should he pronounce divorce for the third time after revoking it twice, the wife will be permanently alienated from him.
The appropriate procedure for divorce, according to the Qur'an and Hadith, is that a person should pronounce one divorce outside the time of the wife's menstrual period. After the first divorce he may pronounce a second in the next clear period if he wants to, though it is preferable that he should confine himself to pronouncing the first. In this case the husband retains the right to revoke the divorce at any time before the lapse of the period of waiting ('iddah) even if the period of waiting has lapsed, the couple have the right to recontract the marriage by mutual consent. If the husband, however, pronounces divorce in his wife's third clear period he has no right to revoke the divorce, and the spouses are not entitled to recontract the marriage. The pronouncing of triple divorce in one session is a highly sinful act acc~rding to the Law, and the Prophet has strongly denounced it. (See Nasii, 'Talaq', 6 - Ed.) It has even been established that 'Umar used to flog those who pronounced triple divorce in one session. Although this procedure of divorce is considered sinful, the founders of the four legal schools consider it to have legal effect, with the result that such divorce, in their view, becomes absolutely irrevocable.
*251). This refers to the mahr (bridal gift) and the jewellery, clothes and so on which the husband offers as a gift to his wife, and to which he has no right of reclaim. It is, indeed, normally inconsistent with Islamic ethics that a person should reclaim anything he has made over to another by way of donation or gift. In the Hadith this disgraceful act is likened to a dog licking its own vomit. (See Bukhari, 'Hibah', 30; Nasiii, 'Hibah', 3, etc. - Ed.)
In the case of a husband, in particular, it is a matter of the utmost disgrace that, at the time of saying farewell to his divorced wife he should try to dispossess her of what he had once given her out of his own goodwill. On the contrary, the morals that Islam seeks to cultivate require that at the time of parting the husband ought to present her with a farewell gift. (See verse 241 below.)
*252). In the terminology of Islamic Law this is known as khul', i.e. a woman's securing the annulment of her marriage through the payment of some compensation to her husband. Whatever settlement is made between a husband and wife should come into effect. If the matter is referred to the court, however, it will investigate only whether the wife has really become too disgusted with the husband to put up with him. (For the Traditions on the basis of which the author concludes this see the commentaries on this verse in Ibn Kathir and Qurtubi, see especially the latter, vol. 2, pp. 946-8 - Ed.) Once this is determined the court is entitled to fix the amount of payment incumbent on the wife as compensation for the repudiation of her marriage, and the husband will be bound to accept that amount and divorce his wife. In general, the jurists believe that the payment, thus fixed, should not be higher than the original mahr paid by the husband.
The divorce that comes into effect is irrevocable and brings separation into effect immediately. Since the woman has paid compensation, she has in effect purchased the right of repudiation and the husband, therefore, has ceased to have the right to revoke the divorce. If, however, the spouses agree to recontract marriage, they may do so.
According to the majority of jurists the period of waiting under khul' is the same as under divorce. However, there are several Traditions in Abu Da'ud, Tirmidhi, Ibn Majah, etc., which show that the Prophet fixed the period of waiting at one menstrual period, and that 'Uthman applied this in a case which he decided. (See Ibn Kathir's commentary on the verse.)