Shaikh Fawzaan (may Allaah preserve him) says: The Callers to misguidance are of many types
The callers to misguidance are of many types. They have means of spreading their call which were not present in the past and many people have been deceived by them. Therefore, what is obligated upon us is to clarify and warn against them. Refute the shubuhaat (i.e. those affairs that are made to resemble the truth but are falsehood in reality); so that the people are saved from their evil or the one who wishes to be saved is saved.
[لِّيَهْلِكَ مَنْ هَلَكَ عَن بَيِّنَةٍ وَيَحْيَىٰ مَنْ حَيَّ عَن بَيِّنَةٍ- So that those who were to be destroyed might be destroyed after a clear evidence, and those who were to live might live after a clear evidence. (8:42)]
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