Tertullian

“ The Connection of the True Christ with the Dispensation of the Old Testament Asserted.
But we now advance a step further on, and challenge (as we promised to do) the very Gospel of Marcion, with the intention of thus proving that it has been adulterated. For it is certain [1] that the whole aim at which he has strenuously laboured even in the drawing up of his Antitheses, centres in this, that he may establish a diversity between the Old and the New Testaments, so that his own Christ may be separate from the Creator, as belonging to this rival god, and as alien from the law and the prophets. ”

“ Hence will arise also our rule, [8] by which we determine [9] that there ought to be nothing in common between the Christ of the rival god and the Creator; but that (Christ) must be pronounced to belong to the Creator, [10] if He has administered His dispensations, fulfilled His prophecies, promoted [11] His laws, given reality to [12] His promises, revived His mighty power, [13] remoulded His determinations, [14] expressed His attributes, His properties. ”