Surah Nisa’ 128. 129 130
And if a woman fears cruelty or desertion on her husband’s part, there is no sin on them both if they make terms of peace between themselves; and making peace is better. And human inner-selves are swayed by greed. But if you do good and keep away from evil, verily, Allah is Ever Well-Acquainted with what you do.
You will never be able to do perfect justice between wives even if it is your ardent desire, so do not incline too much to one of them (by giving her more of your time and provision) so as to leave the other hanging (i.e. neither divorced nor married). And if you do justice, and do all that is right and fear Allah by keeping away from all that is wrong, then Allah is Ever Oft-Forgiving, Most Merciful.
But if they separate (by divorce), Allah will provide abundance for everyone of them from His Bounty. And Allah is Ever All-Sufficient for His creatures’ need, All-Wise.
What Ibn kathir رحمة الله عليه has understood the ayat to mean.
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Islamic Marriage 