Well, we cannot make a subjective personal judgment on whether a bishop is still in office or not; that would be Protestant style. We cannot depose a bishop, and we cannot declare that this bishop has lost his office. This is not the hierarchical structure of the Catholic Church. So in this case, we have to appeal to him and advise him of his errors. And ask him, of course, to respectfully withdraw and renounce his errors. When he will not do this, we have to write to the Pope, because it's only the Pope who is above the bishop. We cannot judge, but a Pope can give canonical judgment to a bishop, and the Pope has the right to do this because of divine institution.
So, in this case, we have to advise the Holy See, and the Holy See has to act in this case. When the Holy See, the Pope, is not acting, then the bishop remains a bishop canonically. But even so, he may personally have already lost faith in theory. In this case, we must not listen to what he says while also praying for his conversion. If he commands us to do something contrary to the faith or the sacredness of the sacraments, we are not required to obey him, but he remains bishop until the Pope deposes him. This is the objective Catholic hierarchical structure.
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