Well the pope is bound by the pronouncements of those before him, by the councils, by the tradition of the church, by scripture, by divine and natural law, etc. He also has no power unless people decide to follow him so there’s that… The popes can also be deposed for heresy like honorius was. Can you please show me where bellarmine said this about checks and balances? I’d like to see what he was actually talking about. I have read quite a few history books on the papacy, and seen a lot of back and forth debates on it. It’s the first time someone has ever said that the time of bellarmine had different papal beliefs than Vatican I.