Part 5/10:
Long before the formal split in 1054, significant theological disagreements emerged between the two branches, particularly concerning the Holy Trinity. The Orthodox Church held that the Holy Spirit proceeds solely from the Father, contrary to the Western Church's addition of the phrase filioque—indicating the Holy Spirit proceeds from both the Father and the Son. This modification, introduced during the 6th Century, became a central point of contention, seen by the Orthodox as both unauthorized and a distortion of the faith.