Final answer:
In 1054, the Great Schism occurred, leading to a major transformation in the relationship between the Eastern Orthodox Church and the Roman Catholic Church. Differences in theological concepts, linguistic and cultural practices, and views about the clergy led to this split. Post-Schism, the Western half became the Roman Catholic Church and the Eastern half became the Eastern Orthodox Church.
Step-by-step explanation:
The relationship between the Eastern Orthodox Church and the Roman Catholic Church underwent a significant transformation in 1054. This year marked the occurrence of the Great Schism, where the church divided into two halves due to theological and cultural differences. The Pope's chief representative had issued a letter excommunicating the Patriarch of Constantinople and his followers due to perceived non-cooperation. In response, the Patriarch excommunicated the Pope's representatives right back.
Post this event, the Eastern church became known as the Eastern Orthodox Church and the Western Church became the Roman Catholic Church. The split was due to the debate over the final authority in the church, language and cultural differences, and the status of the clergy. The Western Church, lead by the Pope, operated in Latin and held that the Pope was the final authority while insisting on a celibate clergy. The Eastern Church, on the other hand, operated in Greek and permitted priests to marry while holding that other patriarchs were equally authoritative as the Pope.
The Great Schism might have been the culmination of the tensions between the two halves, but the disagreements had been increasing over time. Following the Schism, the Popes consistently tried to reunify the two separate halves of Christianity under their authority, insisting supremacy over the Orthodox Church. However, the Orthodox bishops viewed Pope only as first among equals.
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