Nearly all ecclesiastical writers, from Justin to Origen, opposed Marcion. He appeared already to Justin as the most wicked enemy. We can understand this, and we can quite as well understand how the Church Fathers put him on a level with Basilides and Valentinus, and could not see the difference between them. Because Marcion elevated a better God above the god of creation, and consequently robbed the Christian God of his honour, he appeared to be worse than a heathen (Sentent. episc. LXXXVII., in Hartel's edition of Cyprian, I. p. 454; "Gentiles quamvis idola colant, tamen summum deum patrem creatorem cognoscunt et confitentur [!]; in hunc Marcion blasphemat, etc."), as a blaspheming emissary of demons, as the first-born of Satan (Polyc., Justin, Irenæus). Because he rejected the allegoric interpretation of the Old Testament, and explained its predictions as referring to a Messiah of the Jews who was yet to come, he seemed to be a Jew (Tertull., adv. Marc. III.). Because he deprived Christianity of the apologetic proof (the proof from antiquity) he seemed to be a heathen and a Jew at the same time (see my Texte u. Unters. I. 3, p. 68; the antitheses of Marcion became very important for the heathen and Manichæan assaults on Christianity). Because he represented the twelve Apostles as unreliable witnesses, he appeared to be the most wicked and shameless of all heretics. Finally, because he gained so many adherents, and actually founded a church, he appeared to be the ravening wolf (Justin, Rhodon), and his church as the spurious church. (Tertull., adv. Marc. IV. 5). In Marcion the Church Fathers chiefly attacked what they attacked in all Gnostic heretics, but here error shewed itself in its worst form. They learned much in opposing Marcion (see Bk. II.). For instance, their interpretation of the _regula fidei_ and of the New Testament received a directly Antimarcionite expression in the Church. One thing, however, they could not learn from him, and that was how to make Christianity into a philosophic system. He formed no such system, but he has given a clearly outlined conception, based on historic documents, of Christianity as the religion which redeems the world.