Ruling on slandering the daughter of the Prophet (blessings and peace of Allah be upon him)
It is obligatory for the Muslims to respect the Prophet (blessings and peace of Allah be upon him), venerate him and declare him to be above all shortcomings. The religious texts indicate that deliberately speaking ill of the Prophet (blessings and peace of Allah be upon him) constitutes disbelief (kufr). Speaking ill of the daughter is a great offence to the father, especially if the offence takes the form of slander, because people naturally feel that slander of the daughter would undermine the father’s status among people, and he would be shamed by that. Undoubtedly the one who slanders the daughter of the Messenger of Allah (blessings and peace of Allah be upon him) causes great offence to her father (blessings and peace of Allah be upon him) and would undermine his status among people, so deliberately doing that constitutes disbelief (kufr). Please see the details of that and the views of the scholars in the long answer.
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