noun

(used especially between Christians and Muslims) someone who does not have the same religious beliefs as the person speaking:
He lived among infidels/the infidel.
infidel armies
infidel
Someone who refuses to live his/her life according to the terms dictated by an old book which is a compilation of bizarre superstitions and fictitious tales. Infidels usually have a brain of their own and they choose to use it on a daily basis. Some infidels are atheists, some are agnostic and some are spiritual.
Christian priest: Let there be light...
Muslim priest: La ilaha illallah...
Hindu priest: Om namah shivaaya...
Buddhist priest: Om mani padme hum...