5 But perhaps you believe the common report about Christ. Faustus makes a feeble suggestion of this kind as a last resource, to escape being obliged either to produce his worthless authorities, or to come under the power of those opposed to him. Well, if report is your authority, you should consider the consequences of trusting to such evidence. There are many bad things reported of you which you do not wish people to believe. Is it reasonable to make the same evidence true about Christ and false about yourselves?
In fact, you deny the common report about Christ. For the report most widely spread, and which every one has heard repeated, is that which distinctly asserts that Christ was born of the seed of David, according to the promise made in the Hebrew Scriptures to Abraham and Isaac and Jacob: "In your seed shall all nations be blessed." You will not admit this Hebrew testimony, but you do not seem to have any other. The authority of our books, which is confirmed by the agreement of so many nations, supported by a succession of apostles, bishops, and councils, is against you.
Your books have no authority, for it is an authority maintained by only a few, and these the worshippers of an untruthful God and Christ. If they are not following the example of the beings they worship, their testimony must be against their own false doctrine. And, once more, common report gives a very bad account of you, and invariably asserts, in opposition to you, that Christ was of the seed of David. You did not hear the voice of the Father from heaven. You did not see the works by which Christ bore witness to Himself.
The books which tell of these things you profess to receive, that you may maintain a delusive appearance of Christianity; but when anything is quoted against you, you say that the books have been tampered with. You quote the passage where Christ says, "If you believe not me, believe the works;" and again, "I am one that bear witness of myself, and the Father that sent me bears witness of me;" but you will not let us quote in reply such passages as these: "Search the Scriptures; for in them ye think that you have eternal life, and they are they that testify of me;" "If you believed Moses, you would believe me, for he wrote of me;" "They have Moses and the prophets, let them hear them;" "If they hear not Moses and the prophets, neither will they believe though one rose from the dead."
What have you to say for yourselves? Where is your authority? If you reject these passages of Scripture, in spite of the weighty authority in their favor, what miracles can you show? However, if you did work miracles, we should be on our guard against receiving their evidence in your case; for the Lord has forewarned us: "Many false Christs and false prophets shall arise, and shall do many signs and wonders, that they may deceive, if it were possible, the very elect: behold, I have told you before." This shows that the established authority of Scripture must outweigh every other; for it derives new confirmation from the progress of events which happen, as Scripture proves, in fulfillment of the predictions made so long before their occurrence.
Source: Reply to Faustus the Manichaean (New Advent)