Some quick responses when the topic of a sinful Pope comes up from Scott Hahn’s book Reasons to Believe.
Do Catholics think the Pope is sinless? –No. Most Popes go to confession at least once a week. Peter was a sinner but that did not diminish his authority at all.
Do Catholics think that the Pope does not mistakes? –No. Popes make mistakes all the time in daily life. The power of infallibility on applies to matters of faith and morals.
Was the doctrine of Infallibility made up in the 1900’s? –No. The Church Father’s witness to it. It was only in the 1900’s when it was fully articulated and defined. Plus, everyone agrees that the evangelists and writers of the Bible were writing infallibly. Thus, the notion has been around for a long time.
Papal authority was lost by the existence of bad Popes. –No, because as Jesus said the Scribes and Pharisees sit in Moses’ seat so do what they say but not what they do. The authority is given regardless of their merit.
If the Papacy was really that great, there would not have been bad Popes. –No, because even Jesus chose an apostle that would betray him. We can even note, that Judas’ apostleship was continued after him when the group choose another to replace him in acts. The same things would be true for Peter’s role regardless of merit. Jesus leaves everyone Pope or not to choose good or evil.
These insights by Scott Hahn not only provide us with great apologetics, but help us understand the devotion and reverence we should show to even ‘bad’ Popes.