Rorate Caeli

Playing Luther

[I]t is not the pope alone who is always in the right, if the article of The Creed is correct: "I believe one holy Christian Church"; otherwise the prayer must run: "I believe in the pope at Rome," and so reduce the Christian Church to one man, -- which would be nothing else than a devilish and hellish error.

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Balaam's ass, also, was wiser than the prophet himself. If God then spoke an ass against a prophet, why should He not be able even now to speak by a righteous man against the pope? In like manner St. Paul rebukes St. Peter as a man in error. Therefore it behooves every Christian to espouse the cause of the faith, to understand and defend it, and to rebuke errors.

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In short, at Rome, Christ counts for nothing, the pope counts for everything; and yet they would compel us with threats to approve, and praise and honor such antichristian sins, though this is against God and against all Christian doctrine.
Martin Luther 
To the Christian Nobility of the German Nation (An den christlichen Adel deutscher Nation
1520