What is the standard for permissible verbal abuse when necessitated by need or benefit, directed at an unjust ruler responsible for the killing and imprisonment of many? Is it limited to describing him as unjust and a murderer, or does it include more demeaning verbal abuse, even if considered offensive by custom? Is it better to refrain from it?

Islam calls for purity of speech and avoidance of obscenity, for obscenity is not from Islam and is a sign of bad character. Many prophetic traditions have been reported prohibiting obscenity and lewdness, and affirming that Allah does not love the obscene and lewd person. The Prophet, peace be upon him, applied this guidance in his dealings with the Jews and others, and he forbade Aisha from using obscene language, affirming to her that gentleness and leniency are better than violence and obscenity. As for the oppressive Muslim ruler who openly declares his injustice, it is permissible to curse him by mentioning the injustices he has openly declared, while the general principle of avoiding obscene language in other matters remains. This is supported by the Almighty's saying: "Allah does not like the public utterance of evil speech except by one who has been wronged" (Quran 4:148), which indicates the permissibility of uttering evil speech for the wronged person within the limits of explaining his grievance and supplicating against the oppressor, and it does not extend to slander or unlawful backbiting.