Glossolalia, or speaking in tongues, may be considered a normal phenomenon in certain Christian denominations, as divinely inspired, since it is mentioned in the Bible (1 Corinthians, 14:27-33, although St. Paul speaks of the importance of an interpreter, since "God is not the author of confusion"), but it is not confined to Christianity or even overtly religious environments. Others conceptualize glossolalia as a form of automatic speech, usually of a pseudo-language which may be mistaken for a foreign tongue. Such happenings may occur in trancelike states, or in pathological states, such as schizophrenia.
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London: Arnold, 2001: 237-240