The Filioque Controversy

A core issue leading to the schism revolved around the Nicene Creed, formulated at the First Ecumenical Council in 325 in Nicaea, not far from today’s Istanbul, still referred to as Constantinople by the Orthodox community. This creed clarified the church’s beliefs concerning the Trinity, and thus definitions of heresy concerning non-Trinitarian teachings such as Arianism.
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This creed is the bedrock of the worldview through which European peoples came to view reality as the story of Jesus spread from the Mediterranean up through the European peninsular to the islands of Britain, Ireland and Iceland. It is the creed that verbalised Europe’s common heritage, a belief in the Triune God, the original and ultimate expression of unity-in-diversity towards which the European project still strives. It is the creed that made such a dream possible. It is the creed that gave Europe a fundamental unity.
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However, the ‘filioque’ controversy catalised the final rupture in 1054. The Western church first added this phrase as early as 589 to the section of the creed concerning the Holy Spirit ‘who proceeds from the Father’. Translated ‘and the Son’, its inclusion was meant to show that both Father and Son were fully God. But the Western church did not consult the Eastern church about this addition.

The resulting 900-year broken relationship, with mistrust, name-calling and even the sacking of Constantinople by Crusaders, profoundly shaped historical developments of the second millennium, including paving the way for the Ottoman conquest.

Source: Jeff Fountain  -  Weekly Word eNewsletter, 8 April 2019, "The Creed That Unites And Divides"
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