Final answer:
The belief that the Holy Spirit 'proceeds from the Father and the Son' is one of the reasons for the split of the Eastern and Western churches.
Step-by-step explanation:
The reason for the split of the Eastern and Western churches is b. the belief that the Holy Spirit 'proceeds from the Father and the Son.' This theological disagreement over the procession of the Holy Spirit, known as the Filioque controversy, was one of the major factors that led to the Great Schism between the Eastern Orthodox Church and the Roman Catholic Church in 1054.
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