The Pope should not flatter himself about his power nor should he rashly glory in his honor and high estate, because the less he is judged by man, the more he is judged by God. Still the less can the Roman Pontiff glory because he can be judged by men, or rather, can be shown to be already judged, if for example he should wither away into heresy; because he who does not believe is already judged, In such a case it should be said of him: 'If salt should lose its savor, it is good for nothing but to be cast out and trampled under foot by men.'
Pope Innocent IIIBy heart we believe and by mouth confess the one Church, not of heretics but the Holy Roman, Catholic, and Apostolic Church outside which we believe that no one is saved.
Pope Innocent IIIEvery cleric must obey the Pope, even if he commands what is evil; for no one may judge the Pope.
Pope Innocent III