Tafsir of An-Nisa' 4:20

A man, when his eye desired to seek out a new woman, would slander the one he was already married to, accusing her of indecency. He would do this to force her to ransom herself by returning what he had given her, so that he could spend it on marrying another. Thus, it was said: "And if you intend to replace a wife..."

"And you have given one of them a qintār (a great amount of wealth)." A qintār is a vast amount of wealth. It is derived from qantara (to raise something up), from which the word qanṭarah (bridge) is derived, because it is a raised structure. As the poet said: "Like the bridge of the Roman, its master swore / That it would be surrounded until it is built with baked bricks."

It is narrated that Umar (may Allah be pleased with him) stood to deliver a sermon and said: "O people, do not exaggerate the dowries of women. If it were an honor in this world or piety before Allah, the Messenger of Allah (ﷺ) would have been the most deserving of it. He did not give any of his wives more than twelve uqiyah."

A woman stood up and said: "O Commander of the Faithful, why do you forbid us a right that Allah has granted us, while Allah says: 'And you have given one of them a qintār'?"

Umar replied: "Everyone is more knowledgeable than Umar." Then he said to his companions: "You hear me say such a thing, yet you do not correct me until a woman—who is not among the most learned of women—corrects me?"

"...a manifest sin (buhtānan)." Buhtān (slander) is to confront a man with an ugly matter, accusing him of it while he is innocent, because he is yubhat (stunned/bewildered) by it.

The word buhtānan is in the accusative case as a state (ḥāl), meaning "being slanderers and sinners," or as a mafʿūl lahu (an object for which an action is done), even if it is not an intended goal, similar to saying: "He refrained from fighting out of cowardice (jubnan)."

"And they have taken from you a solemn covenant." This refers to the right of companionship and intimacy. It is as if it were said: "They have taken from you a solemn covenant through your intimacy with one another." It is described as "solemn" due to its strength and magnitude. They used to say: "The companionship of twenty days is a kinship," so how much more so is the union and blending that occurs between spouses?

It is also said that it refers to the words of the guardian at the time of the contract: "I marry her to you upon what is in the Book of Allah: to retain her in kindness or release her with goodness."

It is narrated from the Prophet (ﷺ): "Treat women well, for they are captives (ʿawān) in your hands. You have taken them by the trust of Allah and made their private parts lawful by the word of Allah."

"And do not marry those [women] whom your fathers married, except what has already passed. Indeed, it was an immorality and hateful [to Allah] and was evil as a way. Prohibited to you [for marriage] are your mothers, your daughters, your sisters, your paternal aunts, your maternal aunts, brother’s daughters, sister’s daughters, your nursing mothers, your sisters through nursing, the mothers of your wives, and your step-daughters who are under your guardianship..."