Nonbeliever

Infidel (literally "unfaithful") is a pejorative term used in certain religions for those who do not believe the central tenets of one's own religion, are members of another religion, or are not religious.

Infidel is an ecclesiastical term in Christianity around which the Church developed a body of theology that deals with the concept of infidelity, which makes a clear differentiation between those who were baptized and followed the teachings of the Church versus those who are outside the faith. The term infidel was used by Christians to describe those perceived as the enemies of Christianity.

After the ancient world the concept of otherness, an exclusionary notion of the outside by societies with more or less coherent cultural boundaries, became associated with the development of the monotheistic and prophetic religions of Judaism, Christianity and Islam (cf. pagan).

In modern era literature, the term infidel includes in its scope atheists,polytheists,animists,heathens and pagans. Infidel as a concept is sometimes contrasted with the concept of religious pluralism.

The origins of the word infidel date to the late 15th century, deriving from the French infidèle or Latin īnfidēlis, from in- "not" + fidēlis "faithful" (from fidēs "faith", related to fīdere 'to trust'). The word originally denoted a person of a religion other than one's own, specifically a Christian to a Muslim, a Muslim to a Christian, or a Goy to a Jew. Later meanings in the 15th century include "unbelieving", "a non-Christian" and "one who does not believe in religion" (1527).

Christians have historically referred to people outside their religious group as infidels, somebody who has actively rejected the Christian religion. It only became a well established notion in English sometime in the early sixteenth century, when Jews or "Mohammedans"(Muslims), were described as active opponents to Christianity, and as such infidel was seen as term of contempt. In Catholic doctrine, an infidel is one who does not believe in the doctrine at all and is thus distinct from a heretic, who is one seen as having fallen astray from true doctrine, i.e. by denying the divinity of Jesus. Similarly, the ecclesiastical term was also used by the Methodist Church, in reference to those "without faith".

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