Steven,
Who’s interpretation of the Bible do you follow? After all, the Bible is just words on paper unless you interpret what those words mean. I judge from your reference to study bible notes that you accept the editors of that particular Bible’s interpretation of what it means. Who are they? Where did they get their authority to interpret Scripture?
Every constitution needs a supreme court. We would never have finality of meaning without some way of determining what the Bible actually says. That is where the Catholic Church comes in. Through the Church’s teaching body in cooperation with the Pope, the correct interpretation of what the Bible means has been preserved for 2000 years.
To get back to the point of this thread, it is helpful to look at papal infallibility in the negative. Jesus’ promise that the gates of Hades will never prevail is the promise that He will protect the Church, even from the Pope if necessary. Christ will not allow any of those who have the opportunity to actually and substantively change the Church’s teachings to do so.
I don’t understand why people think the concept of papal infallibility is an attempted power grab by the Pope when it clearly is a burden on him. The first instance of “papal” infallibility in action takes place in Matthew 16. The next “scene” after Jesus names Simon bar Jonah “Rock” and makes him His chief steward is the situation where Jesus predicts what will happen to Him, namely that He will suffer and die. Peter attempts to use his new authority and tries to prevent it. Jesus’ response? “Get behind me Satan!” Jesus did not allow Peter to stand in the way of His mission and He won’t let the Successor to Peter stand in the way now.
This is why we can rely on the Church’s interpretation of Scripture. It is because Jesus will never let Her leaders monkey with the true meaning.