The Five Books Against Marcion by Tertullian
Chapter XVIII.--Notwithstanding Their Conceits, the God of the Marcionites Fails in the Vouchers Both of Created Evidence and of Adequate Revelation.
Well, then, he has now advanced into notice, just when he willed, when he could, when the destined hour arrived. For perhaps he was hindered hitherto by his leading star, or some weird malignants, or Saturn in quadrature, or Mars at the trine. The Marcionites are very strongly addicted to astrology; nor do they blush to get their livelihood by help of the very stars which were made by the Creator (whom they depreciate). We must here also treat of the quality of the (new) revelation; whether Marcion's supreme god has become known in a way worthy of him, so as to secure the proof of his existence: and in the way of truth, so that he may be believed to be the very being who had been already proved to have been revealed in a manner worthy of his character. For things which are worthy of God will prove the existence of God. We maintain that God must first be known from nature, and afterwards authenticated by instruction: from nature by His works; by instruction, through His revealed announcements. Now, in a case where nature is excluded, no natural means (of knowledge) are furnished. He ought, therefore, to have carefully supplied a revelation of himself, even by announcements, especially as he had to be revealed in opposition to One who, after so many and so great works, both of creation and revealed announcement, had with difficulty succeeded in satisfying men's faith. In what manner, therefore, has the revelation been made? If by man's conjectural guesses, do not say that God can possibly become known in any other way than by Himself, and appeal not only to the standard of the Creator, but to the conditions both of God's greatness and man's littleness; so that man seem not by any possibility to be greater than God, by having somehow drawn Him out into public recognition, when He was Himself unwilling to become known by His own energies, although man's littleness has been able, according to experiments all over the world, more easily to fashion for itself gods, than to follow the true God whom men now understand by nature. As for the rest, if man shall be thus able to devise a god, -- as Romulus did Consus, and Tatius Cloacina, and Hostilius Fear, and Metellus Alburnus, and a certain authority some time since Antinous, -- the same accomplishment may be allowed to others. As for us, we have found our pilot in Marcion, although not a king nor an emperor.