Is it permissible for ordinary people to label as a kaafir one who reviles Islam, without referring to the scholars concerning that?

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Check below answers in case you are looking for other related questions:
Guidelines on takfeer (ruling someone to be a kaafir)
Misinterpretation of the word of Tawheed, and a false claim that it renders a person free from any need for food

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Related Answers:
There is nothing wrong with using the expression “by chance”
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The Throne is created; Allah, may He be exalted, created it and it is the first and greatest of creations
Guidelines on takfeer (ruling someone to be a kaafir)
Misinterpretation of the word of Tawheed, and a false claim that it renders a person free from any need for food

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