False prophet

A false prophet is any person who claims to be a prophet and either lacks credibility or teaches unbiblical heresy.

The New Testament contains many verses which teach how to tell a false prophet from a true prophet (Matthew 7:15, 1 Corinthians 14:37, 2 Peter 2:1)

Some notable false prophets include the biblical "prophets of Baal" of Canaanite paganism, Simon Magnus the founder of Gnosticism, Muhammed the founder of Islam and Joseph Smith the founder of Mormonism.