Where Does The Authority To Elect A Pope Reside? In the body of Bishops.
Currently, the College of Cardinals elects each successive Roman Pontiff. But this does not occur of necessity. The first Pope, Saint Peter, was “elected” (chosen) by Christ directly. Successive Popes seem to have been chosen simply by the choice of who would lead the diocese of Rome, as the Pope is the Bishop of Rome. At times, the choice of the next Pope was made by a relatively small number of persons, just a handful of Cardinals.
In Universi Dominici Gregis, Pope Saint John Paul II states about a conclave comprised of Cardinal-electors: “this institution is not of its nature necessary for the valid election of the Roman Pontiff”. [UDG preface] In other words, the Church could choose, at some point in the future, a different way of electing the next Pope. However, John Paul II decided to continue the ancient tradition of the Cardinals electing the Pope in a conclave: “I once more affirm that the College of electors of the Supreme Pontiff is composed solely of the Cardinals of Holy Roman Church.” And the reason that the College of Cardinals is fitting is that “the universality of the Church is sufficiently expressed by the College of one hundred and twenty electors, made up of Cardinals coming from all parts of the world and from very different cultures.” [UDG preface] So John Paul II states both that a conclave of Cardinals is not absolutely essential to a valid election, and that, for the time being, this will be the way the Church chooses each Pope.
But do the Cardinals elect the Roman Pontiff as representatives of the whole Church, or as representatives of the body of Bishops? Jesus did not choose only one Apostle, but Twelve. And though Peter is the head of the whole Church, even binding in Heaven what he binds on earth, he leads the Church with the other Apostles, whose successors are the Bishops of the Church. Not every Cardinal is a Bishop, so not every Cardinal is a present-day Apostle, a successor of the Twelve.
When the Church is, for a time, without a successor of Peter, the Church is led by the other successors of the Apostles. Since they hold the authority of Christ as Apostles, the authority to elect the successor of Peter must rest with them. The faithful cannot choose a Roman Pontiff by popular election. For the Bishops are appointed by Christ to rule over the faithful.
Therefore, though the Cardinals have long elected each Roman Pontiff, they do so as representatives of the body of Bishops, in which resides the persistent and irreformable authority to elect each Pope.
Jesus chose the first Pope, Peter. But once He ascended to Heaven, He left that authority with the body of Bishops. The Roman Pontiff can make rules for future conclaves, and so can an Ecumenical Council with the approval of the Roman Pontiff. But they are not constrained to only choose Popes through a conclave of Cardinals.
If a future Pope or Council wished to do so, a conclave could consist of Bishops as well as Cardinals, with Bishops having the same ability to vote for the next Roman Pontiff as any Cardinal. But since there are so many Bishops in the world, the conclave could consist of a subset of Bishops, as long as they represent the body of Bishops dispersed in the world.
Will the Church allow Bishops to vote in a conclave in the near future? In my speculative eschatology, I conclude that She will. As the great apostasy of the first part of the tribulation unfolds, during a time of war and civil unrest, few Cardinals will both remain faithful and be available to travel for a conclave. So the Cardinals will decide, in consultation with prominent Bishops, to make new rules for the conclave, so that Bishops and Cardinals will vote. This conclave will take place in Washington, D.C., in a time when many governments of Europe will be in exile there.
Some persons will claim that this conclave is not valid, as it violates the rules for Councils by being located outside of Rome (which will have been captured in war), and by allowing Bishops to vote. But since the authority to elect a Pope resides with the body of Bishops, they can vote and they can change the rules of the conclave out of grave necessity.
The tribulation draws near. We are at the very threshold. The conservative Catholic schism is well underway. Soon the schismatics will depart, and next many will fall away from Christianity altogether. For when the branch is separated from the vine, it withers. Unfaithful liberal Catholics will also fall away, under the next conservative Pope. The Church will suddenly become much smaller and yet much holier. And the Bishops will elect the successor to the next conservative Pope.
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