Marcionism was an early heresy originated by Marcion of Sinope in A.D. the 2nd century, which rejected the orthodox catholic Christian doctrines of the original Apostolic churches. His doctrine is briefly summarized by Irenaeus of Lyons:
|Marcion of Pontus... developed his teaching, shamelessly blaspheming the God whom the Law and the Prophets proclaimed, describing him as the author of evils, desirous of wars, changing his opinions, and [at different times] contrary to himself. But Jesus [was] from the Father who is above the God that formed the world, and came into Judea in the time of Pontius Pilate, who was procurator of Tiberius Caesar; manifest in human form to those who were in Judea, he abolished the Prophets and the Law, and all the works of that God who made the world, whom he calls the World Ruler. In addition to this he mutilated the Gospel According to Luke, removing everything about the birth of the Lord, and much of the teaching of the words of the Lord, in which the Lord is recorded as clearly confessing the creator of this universe as his Father. He persuaded his disciples that he was more veracious than the apostles who handed down the gospel, giving them not a gospel but a mere fragment of a gospel. He also similarly cut up the Epistles of Paul, removing whatever the apostle said clearly about the God who made the world, that he is the Father of our Lord Jesus Christ, and whatever the apostle teaches by referring to the prophetic writings that predict the coming of the Lord.
Marcionite churches survived for about three centuries in the west, longer in the Byzantine east, but finally died out.
- Theopedia: Marcion
- Strap Store: Marcion
- Early Christian Writings: Marcion
- Catholic Encyclopedia: Marcionites
- The Development of the New Testament Canon: Marcion and the Marcionites (ntcanon.org)
- The Great Heresies a list of heresies committed by Catholics
- OrthodoxWiki: Marcionism
- Tertullian: Adversus Marcionem Against Marcion: 5 Books
- Nag Hammadi & Manichaean Studies: The Panarion of Epiphanius of Salamis, Book I (Sects. 1-46) Second Edition, Revised and Expanded, Translated by Frank Williams. Anacephalaeosis III, 42. Against Marcionites (pp. 294-364) pdf
—scroll down to page 294.