Heretical

Heresy is any belief or theory that is strongly at variance with established beliefs or customs. A heretic is a proponent of such claims or beliefs. Heresy is distinct from both apostasy, which is the explicit renunciation of one's religion, principles or cause, and blasphemy, which is an impious utterance or action concerning God or sacred things.

The term is usually used to refer to violations of important religious teachings, but is used also of views strongly opposed to any generally accepted ideas. It is used in particular in reference to Christianity, Judaism, and Islam.

In certain historical Christian, Islamic and Jewish cultures, among others, espousing ideas deemed heretical has been and in some cases still is subjected not merely to punishments such as excommunication, but even to the death penalty.

The term is from Greek αἵρεσις originally meant "choice" or "thing chosen", but it came to mean the "party or school of a man's choice" and also referred to that process whereby a young person would examine various philosophies to determine how to live. The word "heresy" is usually used within a Christian, Jewish, or Islamic context, and implies slightly different meanings in each. The founder or leader of a heretical movement is called a heresiarch, while individuals who espouse heresy or commit heresy are known as heretics. Heresiology is the study of heresy.

According to Titus 3:10 a divisive person should be warned two times before separating from him. The Greek for the phrase "divisive person" became a technical term in the early Church for a type of "heretic" who promoted dissension. In contrast correct teaching is called sound not only because it builds up the faith, but because it protects it against the corrupting influence of false teachers.

The Church Fathers identified Jews and Judaism with heresy. They saw deviations from orthodox Christianity as heresies that were essentially Jewish in spirit.Tertullian implied that it was the Jews who most inspired heresy in Christianity: "From the Jew the heretic has accepted guidance in this discussion [that Jesus was not the Christ.]" Saint Peter of Antioch referred to Christians that refused to venerate religious images as having "Jewish minds".

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