The Papal Bull of Excommunication in 1054

Humbert, cardinal bishop of the holy Roman Church by the grace of God; Peter, Archbishop of Amalfi; and Frederick, Deacon and chancellor, to all the children of the Catholic Church.

The holy, primary, and Apostolic See of Rome, to which the care of all the churches most especially pertains as if to a head, deigned to make us its ambassadors to this royal city for the sake of the peace and utility of the Church so that, in accordance with what has been written, we might descend and see whether the complaint which rises to its ears without ceasing from this great city, is realized in fact or to know if it is not like this.
Let the glorious emperors, clergy, senate, and people of this city of Constantinople as well as the entire Catholic Church therefore know that we have sensed here both a great good, whence we greatly rejoice in the Lord, and the greatest evil, whence we lament in misery. For as far as the columns of the imperial power and its honored and wise citizens go, this city is most Christian and orthodox.
But as far as Michael, who is called patriarch through an abuse of the term, and the backers of his foolishness are concerned, innumerable tares of heresies are daily sown in its midst.
Because like Simoniacs, they sell the gift of God;

Like Valesians, they castrate their guests and promote them not only to the clergy but to the episcopacy;

Like Arians, they rebaptize those already baptized in the name of the Holy Trinity, and especially Latins;

Like Donatists, they claim that with the exception of the Greek Church, the Church of Christ and baptism has perished from the world;

Like Nicolaitists, they allow and defend the carnal marriages of the ministers of the sacred altar;

Like Severians, they say that the law of Moses is accursed;

Like Pneumatomachoi or Theomachoi, they cut off the procession of the Holy Spirit from the Son;

Like the Manichaeans among others, they state that leave is ensouled (animatum);

Like the Nazarenes, they preserve the carnal cleanness of the Jews to such an extent that they refuse to baptize dying babies before eight days after birth and, in refusing to communicate with pregnant or menstruating women, they forbid them to be baptized if they are pagan;

And because they grow the hair on their head and beards, they will not receive in communion those who tonsure their hair and shave their beards following the decreed practice of the Roman Church.

For these errors and many others committed by them, Michael himself, although admonished by the letters of our lord Pope Leo, contemptuously refused to repent.
Furthermore, when we, the Pope’s ambassadors, wanted to eliminate the causes of such great evils in a reasonable way, he denied us his presence and conversation, forbid churches to celebrate Mass, just as he had earlier closed the churches of the Latins and, calling them “Azymites,” had persecuted the Latins everywhere in word and deed. Indeed, so much [did he persecute them] that among his own children, he had anathematized the Apostolic See and against it he still writes that he is the “Eumenical Patriarch”.
Therefore, because we did not tolerate this unheard of outrage and injury of the first, holy, and Apostolic See and were concerned that the Catholic faith would be undermined in many ways, by the authority of the holy and individuated Trinity and the Apostolic See, whose embassy we are performing, and of all the orthodox fathers from the Seven Councils and of the entire Catholic Church, we thus subscribe to the following anathema which the most reverend Pope has proclaimed upon Michael and his followers unless they should repent.
Michael, neophyte patriarch through abuse of office, who took on the monastic habit out of fear of men alone and is now accused by many of the worst of crimes; and with him Leo called bishop of Achrida; Constantine, chaplain of this Michael, who trampled the sacrifice of the Latins with profane feet; and all their followers in the aforementioned errors and acts of presumption: Let them be anathema Maranatha with the Simoniacs, Valesians, Arians, Donatists, Nicolaitists, Severians, Pneumatomachoi, Manichaeans, Nazarenes, and all the heretics — nay, with the devil himself and his angels, unless they should repent. AMEN, AMEN, AMEN.