Insulting Dead People from the Enemies is Disapproved in Islam
’Ikrima ibn Abi Jahl was an archenemy of the Prophet (PBUH) and Islam, and so was his father. When the Prophet entered Mecca triumphantly, he gave protection to ’Ikrima, and addressed his companions, saying, “’Ikrima is about to come to you as a believer and emigrant. So, do not insult his father. Indeed, insulting the dead hurts the living and does not reach the dead.”