Is Khul' (Redemption from marriage) valid if the wife commits a manifest immorality?

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The Khul' is valid if the wife commits a manifest immorality (fahishah) and offers property to redeem herself from the constraint imposed by the husband for that reason. This validity is established by the statement of Allah the Almighty: "Unless they commit an open immorality" (Quran 4:19), where the exception from the prohibition implies permission. Furthermore, if she commits adultery, there is fear that she might attribute a child from another man to him and corrupt his marital bed, thereby preventing the proper enforcement of Allah's boundaries in his regard. This situation falls under the saying of Allah the Almighty: "And if you fear that they will not uphold Allah's limits, then there is no blame upon either of them for what she redeems herself with" (Quran 2:229). This is one of the two opinions of Al-Shafi'i.