1) The dictionary’s definition
① adherence to a religious opinion contrary to church dogma
② dissent or deviation from a dominant theory, opinion, or practice
③ an opinion, doctrine, or practice contrary to the truth or to generally
accepted beliefs or standards
2) The origin of the word
The word “heresy” comes from the Greek αἵρεσις, hairesis (from αἱρέομαι, haireomai, “choose”), meaning either a choice of beliefs, or a faction of dissident believers.
3) The Bible’s interpretation
Looking in the Bible, let us first locate the verses which mention the word “heresy.”
Gal. 5:20, KJV 『Idolatry, witchcraft…wrath, strife, seditions, heresies,』
2 Pet. 2:1 『…They will secretly introduce destructive heresies…』
Tit. 3:10, KJV『 A man that is an heretick after the first and second admonition reject…』
4) The Doctrine of Christianity
At the time of the Early Church, heresy was considered to be any opinion or doctrine which deviated from the truth of the Early Church, from those who followed only the teachings of Jesus. In other words, the religious organizations that do not follow the words of God, which have been written in the Bible, are heretical.