QuestionWhen is a woman considered to be divorced and what is the wisdom behind the permissibility?Answer
A woman is considered to be divorced when her husband pronounces divorce upon her while he is legally responsible, acting of his own free will, there is no factor preventing him from divorcing her, such as madness, drunkenness or the like, and the woman is purified (following her menses) and her husband has not had sexual intercourse with her during this period of purity and if she is pregnant.
If the husband is insane, acting under duress, or he is drunk (even though he be a sinner, according to the most authoritative of two opinions held by the scholars) or his anger is so intense that it prevents him from comprehending the harms of divorce, due to clear causes supporting his claim of extreme anger, with the presence of absolute reliability on that, or a clear testimony that supports that, then a divorce is not valid in this case, according to the words of the Prophet (Sallallahu Alayhi wa Sallam):“The pen has been lifted regarding three: The minor until he reaches maturity, the sleeper until he awakes and the insane person until he becomes well.” (Abu Dawud no 4403 and At-Tirmidhi no 1423)
And the Words of Allah, the Almighty, the All-Powerful:“Whoever disbelieved in Allah after his belief, except him who is forced thereto and whose hear is at rest with Faith.” (Surah an-Nahl 16: 106)
So if the one who is coerced into disbelief is not a disbeliever as long as his heart is at rest with faith, then it is even more fitting that the divorce of one who is forced against his will – and nothing induced him to divorce except coercion- should not be divorced, in accordance with the words of the Prophet (Sallallahu Alayhi wa Sallam):“There is no divorce and no manumission in (cases of) Ighlaq.”
(Narrated by Ahmad, Abu Dawud and ibn Majah and authenticated by Al-Hakim.)
A group of scholars – including Imam Ahmad (Rahimahullah) explained the word Ighlaq to mean coercion and intense anger. And Uthman (Radhi Allahu Anhu) the righteous Caliph, and a number of scholars ruled that the divorce of a drunkard whose rationality has being altered by the intoxication is not valid, although he is guilty of sin.
As for the wisdom behind the permissibility of divorce, it is the most obvious of things, because the wife may not suit her husband and he might dislike her intensely for numerous reasons, such as weakness of intellect, weakness in religious matters, bad manners and the like. So Allah has made a way out (for him) by divorcing her and removing her from his guardianship as Allah the Most High says:“But if they separate (by divorce), Allah will provide abundance for everyone of them from His Bounty.” (Surah An-Nisa' 4: 130)
Shaikh Ibn Baz (Rahimahullah)
Reference: Fatawa Islamiyah Volume 6 Page 20