Another common misconception confuses infallibility with inspiration. These two charisms are entirely different, though they have, when God willed it, coincided in the same person (e.g., St. Peter, who preached and wrote Scripture infallibly and under the inspiration of the Holy Spirit). The charism of inspiration involves the Holy Spirit providing divine revelation to the recipient. Perhaps the best example of this is found in Scripture. The writers of the Gospels, for example, received in a mysterious way the revlation the Holy Spirit wanted them to set forth with pen and ink. Their human freedom and individual personalities were completely intact, even as God breathed into their minds the revelation He wanted them to Communicate. While the sacred writers, then, lent their own natural abilities to the job at hand, obtaining the Gospel message required no effort on their part - that information was given to them directly by the Holy Spirit. That is what we mean by “inspiraton.”
While inspiration gives information, infallibility protects information. It doesn’t provide the pope with the information he needs to teach (that comes through his own efforts to study and understand the deposit of Faith, just as it does for all other Christians here on earth), but it does make sure that when he does formally teach the doctrines of the Faith, he’ll do so without error. And finally, we should note that infallible pronouncements, whether they come from ecumenical councils or popes, never add to the body of revelation that was “Once for all delivered to the saints” (Jude 3), they just make more explicit what is already there.
At this point, I think it important to explain a bit what papal infallibility is not. First, it does not give the pope the answers to theoligical questions (as inspiration would), nor does infallibility guarantee that he will be proactive and teach what needs to be taught, when it should be taught, in the way it should be taught. Infallibility doesn’t mean that the pope is prompted by God to do or teach something. it doesn’t even guarantee that the pope, when he does teach, will be as effective or persuasive or clear as he should be in what he teaches. Papal infallibility guarantees none of these things. Rather, it is a guarantee that God the Holy Spirit will preserve the pope from formally teaching error.
Much like a steel guardrail that lines the outer edge of a twisty mountain road, put there to keep cars from going over a cliff, the gift of papal infallibility is a divine protection against the catastrophe of the Church careening over the precipice of heresy, even if the pope were to drive recklessly, or, as it were, to fall asleep at the wheel.
Infallibility has nothing what so ever to do with sin. Unfortunately, not everyone realizes that and therefore some people may say, or think things that are simply off target due to the common mistake of confusing infallibility and impeccability - sinelessness. Take St. Peter, for example. He was, at times, a sinful and weak man, yet he was called by God to teach infallibly, in his preaching and in the Scripture he wrote for the Church. In spite of his personal weaknesses, Peter had the charism of infallibility when he taught the Faith officially. The same is true of his successors.
All popes, even the saintly ones, have been sinners in need of God’s mercy and grace. Some, unfortunately, were heavy-duty sinners who seemed to give no thought to the eventual hellfire that awaited them if they refused to repent and change their wicked ways. But even their gross sinfulness didn’t change by one fraction the fact that, as popes, they enjoyed the charism of papal infallibility. They may have lived horrible lives, but they were prevented by this grace of the Holy Spirit from formally teaching error to the Church. Amazing, but true; and we should thank God for that kind of armor-plated protection! Even bad popes cannot wreck the papacy.
Honestly, it would be great if the pope did receive inspiration, direct revelation, from God. It would be marvelous if each pope who has ever sat on the Chair of Peter had been sinless and a model of sanctity for the world. If they had, so many things would have been so much easier. That kind of tidiness never seems to be a part of God’s plan. He works best when his grace works through our human weakness and frailty. Sinlessness as a quality of the popes has never happened. Rather, sinfulness, to some degree, high or low, has always been and will always be the norm for popes (just like the rest of us).
The fact is, the only pope who was inspired and who received revelation from God to be given to the whole Church was Simon Peter. After he went home to the heavenly reward, all the subsequent popes have had to do their job of teaching and preserving the deposit of faith the old fashioned way: They learned it.