What are the matters that necessitate a wife's divorce?

Divorce becomes obligatory in several cases:

1. If a man takes an oath of ila' against his wife (swears to abstain from sexual intercourse with her) and four months pass without him retracting his oath, then he must divorce her. This is based on the Almighty's saying: {For those who swear not to approach their wives is a waiting period of four months; then if they return [to their wives], then indeed, Allah is Forgiving and Merciful. And if they resolve on divorce, then indeed, Allah is Hearing and Knowing} [Al-Baqarah: 226-227]. 2. If the two arbiters appointed to resolve the discord between the spouses determine that the best interest necessitates divorce, then it becomes obligatory at that point. 3. Some jurists hold that divorcing an unchaste woman, or a woman who neglects her religious obligations such as prayer, becomes obligatory if the husband is unable to compel her to perform these obligations.