Marcionism was an Early Christian dualist belief system that originated in the teachings of Marcion of Sinope at Rome around the year 144.
Marcion believed Jesus was the savior sent by God, and Paul the Apostle was his chief apostle, but he rejected the Hebrew Bible and the God of Israel. Marcionists believed that the wrathful Hebrew God was a separate and lower entity than the all-forgiving God of the New Testament. This belief was in some ways similar to Gnostic Christian theology; notably, both are dualistic, that is, they posit opposing gods, forces, or principles: one higher, spiritual, and "good", and the other lower, material, and "evil" (compare Manichaeism), in contrast to other Christian views that "evil" has no independent existence, but is a privation or lack of "good", a view shared by the Jewish theologian Moses Maimonides.
Marcionism, similar to Gnosticism, depicted the God of the Old Testament as a tyrant or demiurge (see also God as the Devil). Marcion was labeled a gnostic by Philip Schaff, while other scholars have rejected that categorization. Marcion's canon consisted of eleven books: A gospel consisting of ten sections that also appeared in the Gospel of Luke; and ten Pauline epistles.
Marcion's canon rejected the entire Old Testament, along with all other epistles and gospels of the 27 book New Testament canon because they transmitted "Jewish" ideas. Paul's epistles enjoy a prominent position in the Marcionite canon, since Paul is credited with correctly transmitting the gracious universality of Jesus' message in opposition to the harsh dictates of the "just god".
Marcionism was denounced by its opponents as heresy, and written against, notably by Tertullian, in a five-book treatise Adversus Marcionem, written about 208. Marcion's writings are lost, though they were widely read and numerous manuscripts must have existed. Even so, many scholars (including Henry Wace) claim it is possible to reconstruct and deduce a large part of ancient Marcionism through what later critics, especially Tertullian, said concerning Marcion.
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