• The dispute over this minute element of doctrine provided a
convenient flashpoint for the political-ecclesiastical rivalries,
cultural distance, misunderstandings, and conflicts that had
extended over centuries.The Final Break
• The final break in 1054 involved naked power plays on the side of
both Rome and Constantinople.
• The papacy insisted on the adoption of Latin liturgical practices
in the Greek churches of southern Italy that had been liberated
from Byzantine control by the Normans. At the same time, the
patriarch of Constantinople forced Latin churches in that city to
adopt the Greek liturgical usages and say the creed without the
additional words.• The head of the Bulgarian church, Leo of Ohrid—encouraged by the
patriarch Michael Cerularius—attacked the Latin practices, which
led Pope Leo IX to send an embassy led by Cardinal Humbert to
Constantinople in 1054.• Cardinal Humbert was abusive and arrogant, and his attitude was
matched in both by the patriarch. On July 16, 1054, Humbert and
his legates laid a statement of excommunication of the patriarch
and his supporters on the altar of the Church of St. Sophia.• By order of the emperor Constantine IX, the statement of
excommunication was burned, and a synod he summoned in
Constantinople excommunicated in return Humbert and his
associates. The schism was final.• Two serious efforts were subsequently made to heal the schism but
with no lasting success.
o The Second Council of Lyon (1274) saw the filioque affirmed
by the Greek delegates, and peace lasted for 15 years, ending
in 1289.