If the oppressed person forgives the oppressor, he has no right to back out
حَدَّثَنَا مُحَمَّدٌ، أَخْبَرَنَا عَبْدُ اللَّهِ، أَخْبَرَنَا هِشَامُ بْنُ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ ـ رضى الله عنها – {وَإِنِ امْرَأَةٌ خَافَتْ مِنْ بَعْلِهَا نُشُوزًا أَوْ إِعْرَاضًا} قَالَتِ الرَّجُلُ تَكُونُ عِنْدَهُ الْمَرْأَةُ، لَيْسَ بِمُسْتَكْثِرٍ مِنْهَا، يُرِيدُ أَنْ يُفَارِقَهَا، فَتَقُولُ أَجْعَلُكَ مِنْ شَأْنِي فِي حِلٍّ. فَنَزَلَتْ هَذِهِ الآيَةُ فِي ذَلِكَ.
Narrated Aisha: Regarding the explanation of the following verse:-- "If a wife fears Cruelty or desertion On her husband's part." (4.128) A man may dislike his wife and intend to divorce her, so she says to him, "I give up my rights, so do not divorce me." The above verse was revealed concerning such a case.