What is the attitude of the scholar of Comparative Religion to religion and religiosity? What is the specific method in Comparative Religion? Does the study of religions differ from other corresponding disciplines? The present volyme tries to answer these questions on the basis of fieldwork among Sinhalese Buddhist monks in Sri Lanka and Orthodox monks and pilgrims on the Holy Mountain of Athos in Greece. Apart from refining a more perceptive view of religion and religiosity, study elucidates the definition of religion and the principles applied in the comparative study of religions by factual cases from these two cultural fields.