In 1054 there was a severe quarrel. The Normans had been forcing the Greeks in Byzantine Italy to conform to Latin usages; the Patriarch of Constantinople, Michael Cerularius, in return demanded that the Latin churches at Constantinople should adopt Greek practices, and in 1052, when they refused, he closed them. This was perhaps harsh, but as Patriarch he was fully entitled to act in this manner. Among the practices to which Michael and his supporters particularly objected was the Latin use of “azymes” or unleavened bread in the Eucharist, an issue which had not figured in the dispute of the ninth century. In 1053, however, Cerularius took up a more conciliatory attitude and wrote to Pope Leo IX, offering to restore the Pope’s name to the Diptychs. In response to this offer, and to settle the disputed questions of Greek and Latin usages, Leo in 1054 sent three legates to Constantinople, the chief of them being Humbert, Bishop of Silva Candida. The choice of Cardinal Humbert was unfortunate, for both he and Cerularius were men of stiff and intransigent temper, whose mutual encounter was not likely to promote good will among Christians. The legates, when they called on Cerularius, did not create a favorable impression. Thrusting a letter from the Pope at him, they retired without giving the usual salutations; the letter itself, although signed by Leo, had in fact been drafted by Humbert, and was distinctly unfriendly in tone. After this the Patriarch refused to have further dealings with the legates. Eventually Humbert lost patience, and laid a Bull of Excommunication against Cerularius on the altar of the Church of the Holy Wisdom: among other ill-founded charges in this document, Humbert accused the Greeks of
omitting the
filioque from the Creed! Humbert promptly left Constantinople without offering any further explanation of his act, and on returning to Italy he represented the whole incident as a great victory for the see of Rome. Cerularius and his synod retaliated by anathematizing Humbert (but not the Roman Church as such). The attempt at reconciliation left matters worse than before.
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