Do not abuse the dead
'Aishah (May Allah be pleased with her) said:
The Messenger of Allah (may the peace and blessings of Allah be upon him) said: "Do not abuse the dead, because they have attained that which they had forwarded (i.e., their deeds, good or bad)."
[Al-Bukhari]
During the pre Islamic period, the Arabs used to boast of their ancestors. This pride leads them to satirize the living and insult the dead. They would incite their poets to mention their merits as well as the defects of others. Their hearts were filled with hatred. The sedition remained, and the drums of war went on overnight; so the war almost ends until it erupts again. However, the tolerant legislations of Islam demolished the tribal – based fanaticism and significantly limited its danger.
The Messenger of Allah (may the peace and blessings of Allah be upon him) taught people how to behave in accordance with the rules of ethics and the best practices until he met his Lord - the Almighty - while the people were on the straight path, from which none deviates except the one who makes a fool of himself.
In the name of faith, their Lord - the Almighty – prohibited them from ridiculing, that is: to disdain and disrespect people. This indicates the arrogance, pride and vanity.
It is forbidden to call each other with offensive names, which one hates to be called with. This is considered dissoluteness, a contradiction of the characteristics of the believers.
What we want to say here is that what is meant is any word that may harm the dead and the living; the insult of the dead hurts their relatives, neighbors, their friends, and others who have merciful hearts.