Ā'ishah (may Allah be pleased with her) reported that the Prophet (may Allah's peace and blessings be upon him) said: "Do not insult the dead, because they have attained the fruits of their deeds."
Sahih/Authentic. - [Al-Bukhari]

Explanation
The Hadīth clearly stresses the prohibition of cursing the dead and speaking ill of their honor; which is considered from the unethical manners. The wisdom behind such prohibition comes at the end of the Hadīth: "Because they have attained the fruits of their deeds." It means they have already seen the consequences of the good or bad deeds they have done before. Therefore, insulting the dead does not harm them; rather, it hurts the living ones.


Benefits
The Hadīth proves that cursing the dead is prohibited. Its general wording suggests that this ruling applies whether they are Muslims or non-Muslims.
Excluded from this prohibition is the case when mentioning the demerits of the dead serves a good purpose.
The wisdom behind this prohibition is clarified in the Hadīth, namely that they are already facing the consequences of their good or bad deeds, and so cursing would avail nothing. It is also because cursing them hurts their living relatives.
One should not speak useless words.



Ibn Umar reported: The Messenger of Allah, peace and blessings be upon him, said, “Mention what is good about your dead, and refrain from speaking about their evil.”

Qays ibn Sa’d reported: A funeral passed by the Messenger of Allah, peace and blessings be upon him, and he stood up. It was said to him, “It is a Jew.” The Prophet said, “Was he not a soul?”

In another narration, the Prophet said, “Verily, you stand to glorify Allah, who is the receiver of souls.”

Unfortunately, nothing concern us with what Mohammed said.

Pipu in your Muslim-Muslim section maybe interested

Biodun556:
Ā'ishah (may Allah be pleased with her) reported that the Prophet (may Allah's peace and blessings be upon him) said: "Do not insult the dead, because they have attained the fruits of their deeds."
Sahih/Authentic. - [Al-Bukhari]

Explanation
The Hadīth clearly stresses the prohibition of cursing the dead and speaking ill of their honor; which is considered from the unethical manners. The wisdom behind such prohibition comes at the end of the Hadīth: "Because they have attained the fruits of their deeds." It means they have already seen the consequences of the good or bad deeds they have done before. Therefore, insulting the dead does not harm them; rather, it hurts the living ones.


Benefits
The Hadīth proves that cursing the dead is prohibited. Its general wording suggests that this ruling applies whether they are Muslims or non-Muslims.
Excluded from this prohibition is the case when mentioning the demerits of the dead serves a good purpose.
The wisdom behind this prohibition is clarified in the Hadīth, namely that they are already facing the consequences of their good or bad deeds, and so cursing would avail nothing. It is also because cursing them hurts their living relatives.
One should not speak useless words.



Ibn Umar reported: The Messenger of Allah, peace and blessings be upon him, said, “Mention what is good about your dead, and refrain from speaking about their evil.”

Well said Bro, may Allah increase you in knowledge.
It also makes a lot of ethical senses, and this can only be better understood and much appreciated by only those who are objective in reasoning.

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