Pope Gregory VII: Banning of Henry IV (Feb 22, 1076)

"And therefore I believe it to be through thy grace and not through my own deeds that it has pleased and does please thee that the Christian people, who have been especially committed to thee, should obey me. And especially to me, as thy representative and by thy favour, has the power been granted by God of binding and loosing in Heaven and on earth. On the strength of this belief therefore, for the honour and security of thy church, in the name of Almighty God, Father, Son and Holy Ghost, I withdraw, through thy power and authority, from Henry the king, son of Henry the emperor, who has risen against thy church with unheard of insolence, the rule over the whole kingdom of the Germans and over Italy. And I absolve all Christians from the bonds of the oath which they have made or shall make to him; and I forbid any one to serve him as king. For it is fitting that he who strives to lessen the honour of thy church should himself lose the honour which belongs to him."

from Gregory VII, Reg. III, No. 10 a, translated in Ernest F. Henderson, Select Historical Documents of the Middle Ages, (London: George Bell and Sons, 1910), 376-377