We report a case involving a 31-year-old Islamic male who murdered his associate under particular circumstances. We took the opportunity to test psychiatrically this man who has been diagnosed in his mother country as a schizophrenic. He came to Japan and was working as a laborer. He is an earnest practicing Muslim. We took an interest in this case because of his bizarre behavior previous to the actual crime. We are interested in the actual method of the murder in relation to Mr. A's cultural and religious background. We demonstrated the significance of the religious cultural knowledge relative to the indigenous ritual for expelling satan and the Islamic pilgrimage to Mekka (Hajj). We conclude that a cultural anthropological and religious viewpoint is necessary in objectively understanding the sources of suffering in patients with mental illness who are from foreign countries.