Marcion was a wealthy ship owner from Sinope on the Black Sea, reportedly the son of a bishop, who arrived in Rome around 140 CE and made a substantial financial gift to the church there before his teaching split him from it. His central claim was that the God described in the Hebrew scriptures, a lawgiver who is just but also jealous, wrathful and inconsistent, cannot be the same God that Jesus revealed as an entirely loving Father previously unknown to the world. On this reading the creator of the material world is a lesser, flawed power, and Christ came from the true, higher God specifically to rescue humanity from the creator's law and from the world the creator had made.
That conviction shaped how Marcion read scripture and, more consequentially, which scripture he accepted at all. He rejected the Hebrew Bible outright as the record of the inferior creator rather than of the true God, and assembled what may be the earliest fixed Christian canon on record: a single edited Gospel, close to Luke but stripped of material he judged corrupted by Judaizing editors, together with ten letters of Paul, whom Marcion regarded as the only apostle who had understood Christ's message correctly. He called the two together the Antitheses and the Apostolikon. Because Marcion's God does not create matter, his Christology tended toward docetism, the view that Christ's body was not fully material and that his sufferings were accordingly not what they appeared to be, though how far Marcion himself pressed this point is argued over by historians working from hostile summaries rather than his own text, which does not survive.