The scientific study of religiosity and spirituality in a psychological context has proven to be quite fruitful over the past years. Authors like Eysenck (1998), Saroglou (2002) or Henningsgaard & Arnau (2008), concentrated on the research of religiosity and spirituality in the context of personality. These authors found especially strong associations between religiosity/spirituality and the personality dimensions Psychoticism, Agreeableness and Conscientousness.However, the question, why these personality characteristics are associated with religiosity and spirituality, remains unanswered until today. To shed some light at this question, the present study compares groups of different approaches to religiosity (catholic, pentecostal and irreligious Subjects) with regard to different measures of religiosity/spirituality, personality, fundamentalism and political opinions.The results show, that, whilst Pentecostals are the most agreeable group, Agnostics, Atheists and Subjects without any religious affirmation present themselves as most open to new experiences and least conservative, when it comes to their political opinions. Catholics can be described as moderate, regarding their religious affiliation. They score in a medium range on almost every used measure of religiosity and spirituality, with somewhat lower scores than Pentacostals, who got the highest outcomes in all of the religious/spiritual measures. The only exception is extrinsic religious orientation, where catholics got the highest scores. Not surprisingly, irreligious subjects obtained the lowest scores in all of the religious measures.The obtained differences in the measures of religiosity/spirituality, personality, fundamentalism, and political conservatism could be accounted for by consulting social and ideological backgrounds of the three examined groups.