Marcionism is a heresy that is attributed to an early church figure by the name of Marcion of Sinope. Marcion was the son of a bishop and moved to Rome about 135 AD. Marcion, who was denounced by the early church fathers including Justin, Irenaeus, Clement of Alexandria, Origen, and Tertullian in the second century, taught a dualistic belief in a distinction between the God of the Old Testament (demiurge) and the God of the New Testament.
According to Marcionism, the God of the Old Testament was a ruthless, bloodthirsty evil God who desired only to pour out His wrath upon creation, whereas, the God of the New Testament was a benevolent savior of love who was opposed to the God of the Old Testament and came to offset the Old Testament God. Marcionite theology teaches that the Old Testament God entrapped creation into a physical universe and that Jesus, unrelated to the Old Testament God and previously unknown to creation, came to free humanity.
Many of Marcion’s teachings align with Gnostic teachings.
Key tenets of Marcionism include:
Jesus was not Jewish, but a spiritual entity
Jesus did not have a physical body (Docetism)
Jesus is not related to the Old Testament God
The Old Testament God is evil, the New Testament God is good
The Hebrew Scriptures have no authority over Christians