Sedevacantists accuse the recent Popes of heresy, and so reject them as invalid popes or antipopes. Restorationists accuse the recent Popes of heresy, claim to accept them as valid popes, but in word and deed reject them just as if they were invalid or antipopes. Restorationists treat every Pope or Council teaching anything they dislike as if they were illegitimate. Both Sedevacantists and Restorationists implicitly but thoroughly reject the indefectibility of the Church.
Sedevacantism is the belief that the See of Peter is vacant. This does not refer to the usual vacancy when one Pope dies or resigns, and the next has not yet been elected. Instead, Sedevacantism is the claim that the See is vacant, while a Roman Pontiff reigns who is accepted by the body of Bishops as the true successor of Peter. The basis for this alleged vacancy is the claim that the Pope, or a series of Popes, are heretics or apostates, and therefore they have lost their authority, and that these Popes have allegedly either never been true Popes or they ceased to be true Popes when they committed heresy or apostasy.
Sedevacantism is necessarily always schismatic and heretical. The Church is apostolic and indefectible. Therefore, the body of Bishops, who are successors to the Apostles, cannot go astray following a false successor of the Apostle Peter. For then the Church would be neither indefectible, nor apostolic, contrary to dogma. The indefectibility of the Church means that the body of Bishops can never defect by following a false Pope who is not truly the successor to the Apostle Peter.
Therefore, every Roman Pontiff who is accepted by the body of Bishops as the true Pope must be the valid successor of Peter. If the election of a disputed Pope is said to be flawed or illegitimate, the acceptance of the Pope in question by the body of Bishop heals in the root any flaws to the election, or in the case of an illegitimate or absent election, this acceptance by the body of Bishops substitutes for that election. Compare the case of Pope Vigilius, as discussed by Saint Robert Bellarmine. So while the authority to elect a Roman Pontiff has long been in the hands of the Cardinal-electors, the source of that authority is the body of Bishops who are the successors of the other Apostles. At a conclave, the Cardinals represent the body of Bishops. The Church has not always had Cardinals, but She has always had the authority to elect Roman Pontiffs, while the Church is without a current Roman Pontiff. Therefore, such authority must reside in the body of Bishops.
Restorationism is not much different from Sedevacantism. Restorationism is just a different and worse version of Sedevacantism. Like the Sedevacantists, the Restorationists accuse multiple Roman Pontiffs of heresy and other grave failings of truth and faith — contrary to dogma on the papal charism of truth and never-failing faith. Both accuse the Church of going astray by the corrupt leadership of Popes and Ecumenical Councils — contrary to the dogma of the indefectibility of the Church. Restorationists and Sedevacantists are heretics for rejecting the indefectibility of the Church and the never-failing faith of the Roman Pontiff.
Both the Sedevacantists and the Restorationists accuse Popes of heresy. But while the Sedevacanists sensibly conclude that any heretical Pope must not be a valid Pope, the Restorationists claim that the Popes they falsely accuse of heresy are valid, but they treat them as invalid. This difference, therefore, is the stupidity of claiming that a Pope guilty of apostasy, idolatry, and heresy could be the valid Vicar of Christ, and at the same time the hypocrisy of treating them as if they had no authority at all. They treat these Roman Pontiffs no different than if they were antipopes or invalid Popes, while claiming that they are legitimate Popes. So, in the end, the Restorationists behave just like the Sedevacantists toward the current and recent Roman Pontiffs.
The fathers and doctors of the Church were correct in teaching that every heretical Bishop loses his jurisdiction (Leo XIII, Satis Cognitum, 15). So, if a Roman Pontiff could be a heretic, he certainly would lose his jurisdiction and become an antipope or invalid pope. However, it is also the teaching of the Church, ancient and constant, that no Pope can ever fail in faith or succumb to heresy. See Catholicism.io for proof of this teaching. Each Pope has the same authority as Peter, and the same never-failing faith as Peter. Therefore, all claims that a Pope failed in faith are false and contrary to dogma. Since no Pope can teach or commit heresy, nor fail in faith in any grave way, no Pope can lose his jurisdiction.
The Sedevacantists falsely accuse Popes of heresy, but at least they draw a conclusion which would be correct if the accusation of heresy were true: that the heretical Pope would lose his authority, like any other heretical Bishop.
The Restorationists are worse than Sedevacantists. For after accusing Pope after Pope of heresy, apostasy, and/or idolatry, they claim that all these accused Popes are valid successors of Peter, and that they have not lost their authority due to these grave failings of faith. Then they refuse to submit to that authority, treating these Popes they call valid as if invalid.
What kind of idiot thinks that a Pope who is an apostate, idolater, and heretic is still the Vicar of Christ, the successor of Peter, the Head of the Church, and the Rock on which the Church is founded? At least the Sedevacantists have a somewhat consistent position. If a Pope were a heretic, he certainly would lose his authority, as even Bellarmine admits. The main error of the Sedevacantists, an error avoided by Bellarmine, is the claim that Popes can fail in faith. The First Vatican Council taught that every Pope has the charism of truth and never-failing faith, which is also the ancient and constant teaching of the Church (and so is of the ordinary universal Magisterium as well as an Ecumenical Council). No Pope can fail in faith by heresy or apostasy or idolatry.
The Restorationists also accuse multiple Ecumenical Councils of heresy (or vaguely accuse these Councils of grave errors), even though every Roman Pontiff has always accepted every teaching of every past Ecumenical Council approved by one of their predecessors. The First Vatican Council clearly taught the supreme authority of the Roman Pontiff, which is without appeal even to an Ecumenical Council. This supreme authority is termed “ultramontanism” by the restorationists. But whatever the term, Vatican I did teach this supreme authority of the Pope. And Lateran V taught that subjection to the Roman Pontiff is from the necessity of salvation. Then Vatican II and current Canon Law confirms this same teaching on this same supreme papal authority. So whether it is called ultramontanism or something else, the teaching is dogma. Rejecting the supreme authority of the Roman Pontiff is heresy.
“So, then, if anyone says that the Roman Pontiff has merely an office of supervision and guidance, and not the full and supreme power of jurisdiction over the whole Church, and this not only in matters of faith and morals, but also in those which concern the discipline and government of the Church dispersed throughout the whole world; or that he has only the principal part, but not the absolute fullness, of this supreme power; or that this power of his is not ordinary and immediate both over all and each of the Churches and over all and each of the pastors and faithful: let him be anathema.” [Pastor Aeternus, chapter 3, n. 9]
The Sedevacantists reject Vatican II, just as the Restorationists do. But at least the Sedevacantists accept the other Ecumenical Councils. By comparison, the Restorationists reject the teachings of many different Ecumenical Councils on the authority of the Roman Pontiff: Florence, Constantinople III and IV, Lateran V, Lyons II, as well as Vatican I and II. Then they accuse Vatican I of teaching heresy, under the guise of rejecting a false interpretation or false spirit of Vatican I. But what they reject as a false interpretation was taught by Vatican I, so plainly and repeatedly, that it could not be interpreted in any other way and has never been interpreted in any other way. The proper interpretation of Vatican I is to believe the wording as plainly stated, that each Roman Pontiff has supreme and universal authority over the Church. See the quote above from Pastor Aeternus.
The actual definition of papal authority in Pastor Aeternus is not restrained or nuanced. The authority of the Roman Pontiff is the authority of Christ which is supreme, full, ordinary, immediate, and includes each and all the churches of the world, and each and all the ordained, religious, and lay faithful, without exception. The Pope has supreme authority by divine right.
Current Canon Law:
“Can. 331 The bishop of the Roman Church, in whom continues the office given by the Lord uniquely to Peter, the first of the Apostles, and to be transmitted to his successors, is the head of the college of bishops, the Vicar of Christ, and the pastor of the universal Church on earth. By virtue of his office he possesses supreme, full, immediate, and universal ordinary power in the Church, which he is always able to exercise freely.”
“Can. 333 n. 3. No appeal or recourse is permitted against a sentence or decree of the Roman Pontiff.”
~ Now I will quote the old code of Canon Law, which fell out of force when the new Code was signed into effect by Pope Saint John Paul II in January 1983. The reason for citing this code is to show that the assertions of the new Code on the supreme authority of the Roman Pontiff is not new:
1917 Code of Canon Law:
“149. The Roman Pontiff as the successor of the Primacy of St. Peter, has not only the prerogative of honor but also the supreme and full power of jurisdiction over the universal Church, in matters of faith and morals as well as in those that pertain to the discipline and government of the Church that extends itself throughout the whole world. This power is truly episcopal, ordinary and immediate, and extends over each and every pastor as well as over the faithful, and is independent from any human authority.”
“150. The Roman Pontiff after his legitimate election obtains at once, from the moment he accepts the election, by Divine right the full power of his supreme jurisdiction.”
“151. Affairs of greater importance, which are reserved exclusively to the Roman Pontiff either by their very nature or by law, are called causae majores.”
“153. There can be no General Council unless it is convoked by the Roman Pontiff. It is the right of the Roman Pontiff to preside, either in person or through others, at the General Council, to determine the matters to be discussed and in what order, to transfer, suspend, dissolve the Council, and to confirm its decrees.”
~ Notice the supreme authority of the Roman Pontiff over Ecumenical Councils. Therefore, it is not possible for an “imperfect Council” to remove a Roman Pontiff, even if the claim is that they are merely acknowledging that God removes him. Each Roman Pontiff has full and supreme authority over every Council, even those that are Ecumenical. Note, however, that, by definition, an Ecumenical Council has the Roman Pontiff as its head. So no Council is truly Ecumenical if the Roman Pontiff rejects that Council. And every Roman Pontiff has the right to refuse to approve one or more or all of the Council’s decisions on doctrine or discipline. Consider, for example, the valid Ecumenical Council of Chalcedon. According to Pope Leo XIII in Satis Cognitum, 15: “The 28th Canon of the Council of Chalcedon, by the very fact that it lacks the assent and approval of the Apostolic See, is admitted by all to be worthless.”
~ The supreme authority of the Roman Pontiff has always been the teaching and discipline of the Church established by Christ, the one holy catholic and apostolic Church. Only recently have some unfaithful persons claimed that this primacy and supremacy of authority is an innovation. In fact, the innovation is their claim against papal authority, which the Church has always taught.
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