Esenţa învăţăturilor lui Marcion, cunoscute sub numele de [[marcionism]], constă în recunoaşterea lui [[Iisus Hristos]] ca mântuitor trimis de Dumnezeu şi a [[Apostolul Pavel|Apostolului Pavel]] ca lider al [[apostoli]]lor, dar şi în respingerea [[Biblie]]i ebraice şi a lui [[Dumnezeu Tatăl|Iehova]]. Se insinuează astfel că Iisus a adus credinţa într-un nou Dumnezeu, diferit de cel descris în [[Vechiul Testament]].
According to Marcion, the god of the Hebrew Bible was jealous, wrathful, and legalistic. The material world he created was defective, a place of suffering; the god who made such a world was the bungling or malicious [[demiurge]]. Jesus was not the [[Mesia]] promised by [[Judaism]]; that Messiah was to be a conqueror and a political leader. Rather, Jesus was sent by a god greater than the Creator. His role was to reveal the transcendent god of light and pure mind, different in character from the creator god of the Hebrew Bible. Jesus's god was free from passion and wrath, wholly benevolent; and Jesus was sent to lead believers out of subjection to the limited, wrathful creator god of the [[Old Testament]].
Marcion produced the first Christian [[canon]], or list of the books of the [[Bible]] that he considered authoritative. His list, however, was much smaller than that currently recognised as valid by most Christians: he included only the [[Gospel of Luke]], the [[Acts of the Apostles]], and ten of the [[epistle]]s attributed to the [[Apostle Paul]]. (He omitted Paul's pastoral epistles, addressed to Timothy and Titus.) These books, according to Marcion, were the ones that contained the true teachings of St. Paul. He completely rejected the [[Old Testament]], believing and teaching that it should not be part of the Christian Bible and was of no value to Christians.