We are looking at the book, Roman but Not Catholic: What Remains at Stake 500 Years after the Reformation by Jerry L. Walls and Kenneth J. Collins

It challenges the Catholic claim to be the only Church that can credibly be linked with Jesus Christ and also the one Church that God set up.  By extension, if that is true then the pope is the real thing.  He is what he claims to be, the vicar of Christ and head of the Church on earth.

Some quotes from the book, 

By the middle of the third century Stephen I, the bishop of Rome from 254 to 257, began to appropriate to himself “all the accumulated prerogatives of Peter” in a dispute with Cyprian and with Firmilian, bishop of Caesarea, though the latter “not only [did] not accept the claim, he seems never to have heard it before.”

After a few false starts and halfhearted attempts by Anicetus, Soter, and Eleutherus, Victor eventually emerged as a full-blown monarchical bishop of Rome around the third quarter of the second century; he distinguished himself by exercising the power and authority normally identified with this office. In the following century the bishop of Rome, Stephen I, began to gather up some of the powers and honors attributed to the apostle Peter, and in a bold move he then turned around and applied them all to himself.

 Indeed, “Stephen’s invocation of Matthew 16 is the first known claim by a pope to an authority derived exclusively from Peter.”

“In effect,” as Arlo Nau observes, “[Stephen] became a Peter redivivus, the Peter of Matthew 16:17–19 reborn.”

 Moreover, though Damasus in the fourth century added to the claims of the bishop of Rome, the full aggregate of such was not yet in place, so he himself was not actually a pope. He was, however, the first to claim that his “see” of ecclesiastical governance was in reality the apostolic see, going back in a supposed succession to the first century. Therefore, although Damasus’s self-perceived authority at the time does, after all, represent something of a transition, he didn’t trouble himself either with the proof of his specific claim of jurisdiction or with the details of church history.

All these bishops of Rome whom we have just considered were relatively minor figures; their importance, remarkably enough, grew by leaps and bounds only after their deaths, when the institution of the papacy eventually came into being in a preeminent way.

Leo was and remained an important bishop in the West: due to the powers and prerogatives he exercised there, especially in the city of Rome itself, Leo may rightly be referred to as a pope. Indeed, in the eyes of some historians Leo in effect constitutes the first pope simply because he exercises so many of the powers and prerogatives that pertain to what actually constitutes this office, at least in the West.

Martin Luther, for his part, believed that it was neither Leo I nor Gregory I but Boniface III. How did Luther come to this judgment? In the early seventh century it was Boniface who was able to convince Phocas, the emperor of the Byzantine Empire, that the Roman bishop, and he alone, was “the head of all churches.”

The following controversial passage from Irenaeus’s Against Heresies has been used to buttress the Petrine claims of Rome and its ecclesiastical power, especially during the fourth century and thereafter. I say, by indicating that tradition derived from the apostles, of the very great, the very ancient, and universally known Church founded and organized at Rome by the two most glorious apostles, Peter and Paul; as also [by pointing out] the faith preached to men, which comes down to our time by means of the successions of the bishops. For it is a matter of necessity that every Church should agree with this Church, on account of its preeminent authority, that is, the faithful everywhere, inasmuch as the apostolical tradition has been preserved continuously by those [faithful men] who exist everywhere.

This material, from the mid-second century, has posed a number of challenges for historians who seek to contextualize it within that temporal framework. First, as Eric Osborn has pointed out, this text, though composed by Irenaeus originally in Greek (only a few fragments remain), has come down to us as a full manuscript only in a later Latin translation composed around 380.

This translation was likely overseen by Damasus I, bishop of Rome, who was also superintending a revision or rewriting of the history of the imperial city in order to include key ecclesiastical events. Is there similarity between the statements of Irenaeus and the ecclesiastical realities of Rome during the fourth century? Can historians even pose such a question? Second, the passage from Irenaeus above indeed contains factual error, as Oscar Cullmann noted in his own day: “The Roman church in any case was not founded by Paul. That is entirely clear from his letter to the Romans.”

Beyond this, as one judges the content of Paul’s Epistle to the Romans, especially those to whom the apostle sends greetings at the end of his letter (he does not greet Peter), it is clear that the church was already well established before Peter arrived. Together, these errors detract from the historical accuracy and therefore from the credibility of this material, raising further doubts for any interpreter. Third, J. B. Lightfoot observes that the language of “the succession of bishops” is employed by Irenaeus in the second century in a much different way than by the later church, that is, as the bricks and mortar of a far more developed hierarchical structure. “In other words, though he [Irenaeus] views the episcopate as a distinct office from the presbytery,” Lightfoot argues, “he does not regard it as a distinct order in the same sense in which the diaconate is a distinct order.”

In fact, Lightfoot continues, Irenaeus “seems to be wholly ignorant that the word bishop had passed from a lower value since the apostolic times.”

Fourth, in the nineteenth century Alexander Roberts, James Donaldson, and A. Cleveland Coxe questioned how the Latin phrase Ad hanc enim ecclesiam propter potiorem principalitatem necesse est omnem convenire ecclesiam (“For it is a matter of necessity that every church should agree with this church, on account of its preeminent authority”) should be translated and interpreted. They maintain, “It is impossible to say with certainty of what words in the Greek original ‘potiorem principalitatem’ [preeminent authority; literally, preferential prominence] may be the translation.”

In the face of such ambiguity they conclude, “We are far from sure that the rendering given above is correct, but we have been unable to think of anything better.”

Finally, regarding the last phrase of this much-debated paragraph (hoc est eos qui sunt undique fideles, in qua semper ab his qui sunt undique conservata est ea quae est ab apostolis traditio, or “the faithful everywhere, inasmuch as the apostolic tradition has been preserved continuously by those [faithful men] who exist everywhere”), J. N. D Kelly offers a rendering that views Rome as neither the source nor the guardian of proper doctrine but instead as its exemplification. He reasons: “Hence it seems more plausible to take in qua with omnem . . . ecclesiam [the faithful everywhere] and to understand Irenaeus as suggesting that the Roman church supplies an ideal illustration.”

Kelly, therefore, concludes his analysis of this pericope, drawn from the writings of Irenaeus, by affirming, “There is therefore no allusion to the later Petrine claims of the Roman see.”

 Indeed, given the doubts and the ambiguity that surround this passage, it is difficult to find a solid basis for the considerably broader claims to ecclesiastical power and privilege that came later.

In addition, Eamon Duffy explains, “Nor can we assume, as Irenaeus did, that the Apostles established there a succession of bishops to carry on their work in the city, for all the indications are that there was no single bishop at Rome for almost a century after the deaths of the Apostles. In fact, wherever we turn, the solid outlines of the Petrine succession at Rome seem to blur and dissolve.” Eamon Duffy, Saints and Sinners: A History of the Popes, 4th ed. (New Haven: Yale University Press, 2015), 2.

As Christopher M. Bellitto, a Roman Catholic scholar, puts it, “The pope could make infallible statements [when he speaks ex cathedra] on faith and morals on his own authority.”Again, Bellitto writes: “The pope had the final say, he could judge all things and all persons, but he himself could be judged by no one.”

He also takes care to point out that infallibility is often confused with certitude and insists that the argument for probable infallibility is not an attempt to achieve certitude.

Dictatus Papae, was actually written by Gregory VII himself. At any rate, it was indeed listed in his papal register in 1075, and as a consequence this artifact does appear to represent Gregory’s own views. Since the Dictatus Papae is a good window on the papacy (as an institution that was made up of numerous claims that slowly emerged and that were repeated over time), it will be cited at length.

The relevant articles are as follows:

1. That the Roman church was founded by God alone.

2. That the Roman pontiff alone can with right be called universal.

8. That he alone may use the imperial insignia.

9. That of the pope alone all princes shall kiss the feet.

10. That his name alone shall be spoken in the churches.

11. That this is the only name in the world.

12. That it may be permitted to him to depose emperors.

16. That no synod shall be called a general one without his order.

17. That no chapter and no book shall be considered canonical without his authority.

19. That he himself may be judged by no one.

22. That the Roman church has never erred; nor will it err to all eternity, the Scripture bearing witness.

26. That he who is not at peace with the Roman church shall not be considered catholic.

It does not insist that popes must be perfect, or even that they would all be model Christians, although the latter might be a reasonable expectation given the NT criteria and qualifications for elders and bishops (1 Tim. 3:1–7). We might reasonably expect that the “chief shepherd,” the bishop of bishops, would meet the NT criteria for bishops. However, the statement does not insist on this, but merely says that they should all be persons of moral integrity, with a sincere love for Christ and the gospel.

The better comparison is not between the OT kings and the papacy but between the OT prophets and the papacy. When we consider the OT prophets, all who are recognized as true prophets were indeed persons of basic moral integrity and genuine love for God, even prophets like Jonah, who were less than perfect in reflecting God’s love and grace. If all the prophets whom God called were persons of integrity and true faith, it hardly seems too much to think that all the “chief shepherds [should be the same]