Tertullian

“ Now, if this question also had entered into dispute, surely it would be found in the apostle, and that too as a great and vital point. No doubt, after the time of the apostles, the truth respecting the belief of God suffered corruption, but it is equally certain that during the life of the apostles their teaching on this great article did not suffer at all; so that no other teaching will have the right of being received as apostolic than that which is at the present day proclaimed in the churches of apostolic foundation. ”

“ Show us, then, one of your churches, tracing its descent from an apostle, and you will have gained the day. [10] Forasmuch then as it is on all accounts evident that there was from Christ down to Marcion’s time no other God in the rule of sacred truth [11] than the Creator, the proof of our argument is sufficiently established, in which we have shown that the god of our heretic first became known by his separation of the gospel and the law. Our previous position [12] is accordingly made good, that no god is to be believed whom any man has devised out of his own conceits ”