Can denouncing evil only be done with the permission of the ruler?

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Check below answers in case you are looking for other related questions:
Guidelines on forms of the cross that are prohibited
Is it permissible for a Muslim to study in a college where there are crosses on the walls of the classrooms?

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Guidelines on forms of the cross that are prohibited
Is it permissible for a Muslim to study in a college where there are crosses on the walls of the classrooms?

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