How to tell the Real Pope from the Anti-Popes?

There can only be one real Pope at a time; this has been true ever since Jesus gave St.Peter the keys to Heaven and Earth.

However, during various points in The Middle Ages, there was more than one people claiming to be Pope of The Catholic Church. This weakened The Church as a whole, at one point creating a Western Schism (an event which almost split The Church in three, and which lead to the disastrous Protestant Reformation).

While it is easy to tell the Popes from the Anti-Popes in hindsight, it is less easy to do when it is actually happening. When in a situation similar to The Western Schism, how would a Good Catholic go about determining which Pope is real and which Pope is false?

The difficulty is great, as you say. The western schism was resolved by the lawful pope and rival anti-popes resigning, and a new undisputed pope being elected. The election process was greatly formalized to prevent future ambiguity.

While the lawful pope was likely discernable based on the circumstances of election, the ongoing risk of confusion and doubt was too great.

My opinion is that God never permits any antipope (false claimant to the papacy) to be accepted by all the Bishops and dioceses of the world. For the Church is indefectible.

Also, no validly elected Pope can become an antipope by some sin or decision that he makes. Once valid, always valid, until death or resignation.

Yes, but the Council of Constance, when the resignations and election happened, was called for by one of the anti-popes, John XXIII. Yet, this council was considered ecumenical and binding in its condemnation of John Hus.

The fact of the matter is that the Holy Spirit is not limited by Canon Law and even by Church tradition (note the lowercase “t”).

Pax Christi

Well, I think that there is still a man in Kansas who claims to be the valid pope. But, as far as I’m concerned, it’s pretty easy to tell that he’s not.

The problem was that with the anti-popes of the Late Middle Ages, neither the validly elected Pope nor the anti-popes had been accepted by all the dioceses in the world (most of them, of course, at the time, were in Western Europe). In fact, IIRC, antipope John XXIII (not to be confused with the validly elected Pope St. John XXIII - elected several hundred years later) was accepted by more bishops as pope than the actual pope at his time. In fact, it wasn’t until Pope St. John XXIII chose the name of John XXIII that the entire matter was finally laid to rest. In addition, most of the laity at the time were poorly educated (being primarily educated in a trade and the basic math needed to operate the trade - but not in reading or writing). So they had to follow the direction of their bishops to discern. Unfortunately, many bishops made their decisions based on political reasons - for example, French bishops backed the Avignon antipope line, while English bishops backed the Roman papal line primarily because France was England’s long-time enemy.

An antipope (John 23) attempted to called an Ecumenical Council at a time when there was much controversy about who the valid Pope may be. But those assembled at Constance did not constitute an ecumenical council until the bull of Gregory XII (true pope) was proclaimed on 4 July 1415.

I’m just pointing out that history shows that events were rather messy and confusing and that the default ultramontanism is not helpful. As a matter of fact, it takes away from the glory of the Holy Spirit, the true protector of the Church.

Pax Christi

Bishops can meet for any purpose. Who calls them is irrelevant. It is ratification by a sitting pope that make them ecumenical. The sitting pope’s participation is evidence of his acceptance, although more explicit documentation may exist.

The true Pope Gregory XII, convoked the council and authorized the sessions from 4 July 1415, and declared the first thirteen previous sessions null and void. Since Pope Gregory XII resigned, Pope Martin V ratified the succeeding sessions at the conclusion. The condemnation of John Hus was in session 15 so it was in the valid sessions.

Exactly. The first seven (often called the ecumenical councils, as they are the only 7 recognized by the Eastern Orthodox - though the Oriental Orthodox only recognize the first 3) were all called by the Roman Emperors. They were then ratified by the popes (and all the bishops in attendance).

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