Thought experiment: If a validly elected pope were to publicly proclaim that “There is no God but Allah, and Muhammad is his prophet,” and follow that up with a personal pilgrimage to Mecca, that is to say, he made it abundantly clear that he no longer personally believed the Catholic faith without making any sort of ex cathedra statement, would he cease to be the pope?
What if he simply said that the Trinity is not true, and that there is only one person in God, but again, not in any ex cathedra sort of way?
What if he said that there are actually four persons in one God: Father, Son, Holy Spirit, and Satan?
How obvious would his heresy have to be for an ordinary Catholic to be able in good conscience to declare that he had lost the papacy?
Blasphemy: Pope Francis Makes Jokes About God
“In the meeting, the pope jokingly likened this to the way the Holy Trinity functions. ‘Inside the Holy Trinity they’re all arguing behind closed doors…but on the outside they give the picture of unity.’