What do we really believe about the Pope and Papal Infallibility? We don't believe that Pope will teach clearly, or even teach everything that he should teach; we don't believe that he won't make a mess of things -- what we do believe, is that when he invokes his supreme authority and teaches infallibly, he will not state what is false (he may not speak the truth clearly, but he won't actually teach what is false).
We also don't believe that the Pope is chosen by the Holy Spirit, or that he is "the best man for the job". But, whoever the Cardinals choose, even if he isn't the best man for the job, even if he is very weak or sinful -- the Holy Spirit will preserve him from leading the Church into error.
This is the gift of the Papacy: The gates of hell will never prevail even against the bad Popes. And that proves that God is the one who truly guides the Catholic Church.
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