Emulating types of religions under specific guidelines doesn't harm anyone. If you break any common sense rules to, you know, go beyond the basics of roleplaying and take extremist/discriminatory views of said religion/belief into your roleplay, then it changes from roleplay to an outright attack on members of the religion/belief.
This being said, there doesn't need to be an extra rule added to this massive list of rules, as many other rules already clear the wrongdoings of this type of roleplay. Basically, do it, but do it respectfully and not in a way that isn't discriminatory to said religion/belief. It's really just common sense...
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