(I originally asked the same question but it was answered only by Shi'a brothers. Since there were no Sunni answers, I accepted that answer and opened this new question requesting a Sunni view.)
Why Sunni Islam does not require witnesses for divorce? It is such an important turning point in one's life and it must require witnesses. There are cases where couple live together even though the husband has issued verbal divorce. But they still live together because of either shame or the difficulty they have to go through if separated. Shi'a Muslims refer to this verse to justify that witnesses are required in divorce:
Thus when they fulfil their term appointed, either take them back on
equitable terms or part with them on equitable terms; and take for
witness two persons from among you, endued with justice, and establish
the evidence (as) before Allah. Such is the admonition given to him
who believes in Allah and the Last Day. And for those who fear Allah,
He (ever) prepares a way out,
This ayah is referring to taking two persons(one from each side) to solve the matter in good manner, as said in first part of the verse, if things get resolved in good manner that's great, but if they does not get settled, they should be separated. Their is no CONDITION mentioned here in this verse for a valid divorce to have witnesses. Though by this verse, it's better this way(because their will be a chance of settlement without divorce). But no obligation or necessity is mentioned here(or anywhere)
Al-Shawkaani (may Allah have mercy on him) said concerning the issue
of having witnesses to taking the wife back: Among the evidence that
it is not essential is the fact that there was scholarly consensus
that it is not essential to have witnesses to divorce, as was narrated
by al-Muwazi‘i in Tayseer al-Bayaan. And taking back the wife is of a
similar nature, so it (having witnesses) is not essential in that case
as it is not essential in the case of divorce. End quote from Nayl
The translation (Sunni), along with brief explanation is as under:
So when they are about to reach their appointed term, hold them back with kindness (1) or separate them with kindness (2), and make two just men among you as witnesses (3), and establish the testimony for Allah (4); with this is advised whoever believes in Allah and the Last Day (5); and whoever fears Allah (6) – Allah will create for him a way of deliverance (7). [62:2]
For less than three divorces, husband can turn back to relation within the term. And if he divorced three times, he can't return back to relation and divorce will apply.
Kindness. It reveals to deal women with kindness, don't harass them if you are already intended for separation. Let the term pass. This also reveals that giving all 3 divorces at once is not kindness, though at once, 3 divorces will immediately apply. Such act is considered too detestable.
[Your Answer], For divorce, or back to relation (if not 3rd divorce), it is good to have witness, but this is optional. Witness must be Practising Muslim, 2 Men, or 1 man and 2 women. (I believe witness is optional because, unlike marriage, divorce is more of spouses' internal/personal concerns than society's concern. In marriage, witnesses are must.
Establish witness for pleasure of Allah, not for personal interests. This reveals taking money or payment to become a witness is Haram (unlawful).
Shariah only applies on Muslims, i.e. who believe on the day of judgement.
Fear Allah: Means have mercy on women. Don't divorce all at once. If you intend to do so, give a gap of a period in each. (So, you may think again and take back decision). Be kind, don't expel woman out of home until term ends and don't try to expand the term intentionally. Make a witness on Divorce or Ruju'.
Such that, after divorce, Allah may create kindness in hearts, so you can turn back (if not third divorce). Or give a more better spouse in Future. Or lessen the burden of life or life after death with His mercy.
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