There is no more harm in adultery than in rubbing one's hands together.

Silence is the genius of fools and one of the virtues of the wise.

There is one fold and one shepherd.

If, therefore, the Greeks or others say that they are not committed to Peter and to his successors, they necessarily say that they are not of the sheep of Christ, since the Lord says that there is only one fold and one shepherd (Jn.10:16). Whoever, therefore, resists this authority, resists the command of God Himself.

We are compelled, our faith urging us, to believe and to hold—and we do firmly believe and simply confess—that there is one holy Catholic and Apostolic Church, outside of which there is neither salvation nor remission of sins.

Therefore, if the earthly power errs, it shall be judged by the spiritual power ... but if the supreme spiritual power errs it can be judged only by God, and not by man ... Therefore we declare, state, define and pronounce that it is altogether necessary to salvation for every human creature to be subject to the Roman pontiff.

Anything done for another is done for oneself.