Matthew 16:18

like the Papal Bull Dum Diversas:

Here’s more info on the bull, in which the following bulls can be read to understand more clearly.

Infallible teachings are open to discussion as to their full implications and the relationship between the dogma and other teachings. Some difference of opinion on interpretation of a dogma is also possible.

Suppose a single Bishop teaches, with his episcopal authority, an idea as a truth on faith or morals, implicit, he says, in Tradition or Scripture. It is then of the non-infallible magisterium. As other Bishops teach the same idea, it is still non-infallible. Then the Pope teaches the idea, perhaps still non-infallibly. Once the Pope and the body of Bishops, dispersed through the world, teach the same idea, as one doctrine, definitively to be held, it becomes infallible under the ordinary and universal Magisterium.

So the idea begins as very open to debate, and as it becomes more firmly taught, by more Bishops, it increases in authority and surety, narrowing the possibility for debate. Then eventually it may be defined infallibly.

That is exactly what happened with the dogma of the Immaculate Conception. Originally, the correct understanding was a minority opinion (famously rejected by St. Thomas in the Summa). It grew in support among theologians and the faithful, began to be taught by individual Bishops – becoming then a non-infallible teaching rather than an opinion – and finally it was defined infallibly under papal infallibility.

But along the way, the idea may develop and improve, as more Bishops weigh in and as the Pope contributes his understanding. So the original idea may change over time. But nothing prevents an idea from having some flaws when it is first proposed by the Magisterium non-infallibly.

Not slavery? Are you kidding me? What do you think Afonso V was doing? This was all about conquest of North Africa. And here is a quote from a subsequent bull Romanus Pontifex:

since we had formerly by other letters of ours granted among other things free and ample faculty to the aforesaid King Alfonso – to invade, search out, capture, vanquish, and subdue all Saracens and pagans whatsoever, and other enemies of Christ wheresoever placed, and the kingdoms, dukedoms, principalities, dominions, possessions, and all movable and immovable goods whatsoever held and possessed by them and to reduce their persons to perpetual slavery, and to apply and appropriate to himself and his successors the kingdoms, dukedoms, counties, principalities, dominions, possessions, and goods, and to convert them to his and their use and profit – by having secured the said faculty, the said King Alfonso, or, by his authority, the aforesaid infante, justly and lawfully has acquired and possessed, and doth possess, these islands, lands, harbors, and seas, and they do of right belong and pertain to the said King Alfonso and his successors, nor without special license from King Alfonso and his successors themselves has any other even of the faithful of Christ been entitled hitherto, nor is he by any means now entitled lawfully to meddle therewith.

And to your earlier question: how did I come to my earlier conclusion that this was immoral? Simple: I’m not a relativist.

Invading, searching out, capturing, vanquishing, subduing, and reducing people to perpetual slavery while conquering land is never a moral thing to do. To argue that relative to the time, it was an acceptable practice, that’s relativism.

The traditional interpretation of the gates of hell passage is that the Church is indefectible:

“Among the prerogatives conferred on His Church by Christ is the gift of indefectibility. By this term is signified, not merely that the Church will persist to the end of time, but further, that it will preserve unimpaired its essential characteristics. The Church can never undergo any constitutional change which will make it, as a social organism, something different from what it was originally. It can never become corrupt in faith or in morals; nor can it ever lose the Apostolic hierarchy, or the sacraments through which Christ communicates grace to men. The gift of indefectibility is expressly promised to the Church by Christ, in the words in which He declares that the gates of hell shall not prevail against it.”

Jumping in here with two points. Firstly, the CCC contained an error in its first edition on the subject of lies and morality: “To lie is to speak or act against the truth in order to lead into error someone who has the right to know the truth.” The bolded text was dropped from the revised (current) edition. It is an error to say that a false assertion is only a lie if the person has a right to the truth. Errors in Church teaching are possible, but only in the non-infallible teachings. However, the Holy Spirit protects the non-infallible teachings from ever erring to such an extent as to lead the faithful away from the path of salvation. So these errors are not of Satan, as you suggest.

Also, the Church teaches (LG 25) that individual Bishops do not have the prerogative of infallibility, and that not every teaching of the Pope is infallible. Vatican I taught the conditions under which a teaching of the Pope is infallible; short of those conditions, his teaching is reliable, not necessarily entirely free from error.

Secondly, Caiaphas in John 11 is another good example of sinful leader who nevertheless can teach truth.

{11:49} Then one of them, named Caiaphas, since he was the high priest that year, said to them: “You do not understand anything.
{11:50} Nor do you realize that it is expedient for you that one man should die for the people, and that the entire nation should not perish.”
{11:51} Yet he did not say this from himself, but since he was the high priest that year, he prophesied that Jesus would die for the nation.

This was a foreshadowing of the principle that a Pope can be sinful and yet teach truth. Caiaphas condemned the Messiah to death (and I propose that he actually knew that Jesus was the Messiah and condemned him anyway). Yet he was able to prophesy truth about Jesus by the grace and providence of God.

Well, for sure we can deduce it was response to the power and aggression of the Turkish Empire at the time. This is what I’m saying about understanding this in sequence. The same Pope condemned the handling of these people also. So its a matter of understanding servitude as opposed to slavery. Have Christians gotten out of hand historically? Look at Mexico, and Columbus didn’t come here to the USA for nothing.

However, did you notice how he started the bull…

“successor of the key-bearer of the heavenly kingdom”

I think I understand what you’re saying. Don’t agree 100%, but I think I understand. It still seems to be reading quite a bit into the phrase “the gates of Hell shall not prevail”. As I stated in a previous post, I see a gate prevailing in a battle is when you are on the offensive. So I read this statement more as when the Church is on the offensive and Hell is on the defensive, then the gates of Hell won’t prevail. What exactly does that mean? I don’t know for sure.

Out of curiosity, where do your views on this passage come from? I’ve read similar statements elsewhere, so I’m wondering if this is just the prevailing explanation/understanding today, or this has actually come from a Saint, Pope, Church document, etc.


Commanding evil while using an authority position and invoking Jesus’s name is taking the Lord’s name in vain.

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