In this article the authors present through theory and case reports on the phenomenon of glossolalia, the unusual vocal utterances that sound language-like. Sense, meaning and function of glossolalia are closely connected with social and cultural context, and therefore glossolalia is experienced as a normal and expected behavior in religious prayer groups, while in mental disorders it is considered a psychopathological symptom. Historic theological debates explain the pure spiritual etiology of glossolalia, while the current studies present the phenomenon of glossolalia as a result of learned behavior and training. Glossolalia occurs as an individual or a group phenomenon after which the speaker and the persons around him feel good, what is explained psychodynamically as a regression upon early developmental levels. In this temporary regression there is an explanation of positive, almost psychotherapeutic effect of glossolalia.