Synonyms for Unworldly (same or very similar meaning)
WordNet sense 1 (concerned with or affecting the spirit or soul):
spiritual, unearthlyWordNet sense 2 (not wise in the ways of the world):
unsophisticatedWordNet sense 3 (marked by or showing unaffected simplicity and lack of guile or worldly experience):
naif, naiveFrom the ODE community, based on WordNetadd/edit