What is the traditional exegesis of the Almighty's saying, "So there is no blame upon either of them for what she gives to secure her freedom," and what is Islam's stance on the law of Khulʿ?

If the wife is obedient and content, it is not permissible for the husband to harm her in order to exact a ransom from her, and whatever is taken from her in such a case is unlawful (haram). However, if the rebellion (nushuz), hatred, and injustice originate from her side, then it is permissible for him to take what she offers him in exchange for their separation. The hadith of the wife of Thabit ibn Qays (sister of Abdullah ibn Ubayy), whom the Prophet, peace and blessings be upon him, granted a khul' (divorce initiated by the wife), is considered the fundamental principle for khul'. Any law regarding khul' that contradicts Islamic law is not permissible to act upon.