Nowhere is it written that to disagree with the Pope is a grave sin. That is not Catholic teaching. It is incorrect. It is only when you disagree with an infallible ex cathedra pronouncement of the Pope that this becomes a grave sin, because in that case, it is heresy. In such a situation, the Pope is not giving his own opinion; he is proclaiming the teaching of the Church definitively, speaking not in his name but in the name of the entire Church. To reject that is to reject the Church's infallible teaching, and that is heresy, which is also a mortal sin.
However, in other cases, if you have a valid reason, you can disagree with or even disobey the Pope. This must be done only when it is evident that what the Pope is saying contradicts the constant teaching of the Church, or when what he says is so ambiguous that it undermines that teaching. Additionally, when the Pope speaks on topics outside his competence, such as science, for example, climate change, or politics, these are not matters that fall under the divine mission of Saint Peter and his successors. Therefore, Catholics are not obliged to agree with the Pope on those matters, and they may respectfully disagree.
The first recorded case of disagreement with a Pope was by Saint Paul the Apostle. He publicly disagreed with Peter in Antioch because of Peter’s ambiguous and scandalous behavior. Peter behaved differently toward Jewish Christians and Gentile Christians, which created confusion and scandal. Paul openly and fraternally corrected him.
We also have the case of Saint Athanasius the Great. He disobeyed and disagreed with the Pope of his time, Pope Liberius, who wanted to force him to make peace with heretical Arian bishops. Saint Athanasius refused, saying he could not do this. As a result, Pope Liberius possibly excommunicated Athanasius. But Athanasius did not commit a sin by disobeying; on the contrary, his action was later recognized by the Church as heroic and meritorious, while the Pope’s action was a grave error.
So, we must distinguish clearly: in which cases we can disagree with the Pope, and in which cases we cannot.
Dear visitors of Gloria Dei and all who have already written or who will write a personal message to me. I am grateful for your attention, your kindness, for your spiritual support and especially for your sacrifices and prayers for me. God may reward you!
