Among the issues that have divided Eastern and Western Christians throughout the centuries, few have had as long and interesting a history as the question of the filioque. Christians everywhere confess their faith in the ancient words of the Nicene Creed. But rather than serve as a source of unity, the Creed has been one of the chief sources of division, as East and West profess their faith in the Trinitarian God using different language. In the Orthodox East, the faithful profess their belief in "the Holy Spirit, who proceeds from the Father." In the West, however, they say they believe in the Holy Spirit, who proceeds from the Father "and the Son"-in Latin "filioque."
For over a millennium Christendom's greatest minds have addressed and debated the question (sometimes in rather polemical terms) in the belief that the theological issues at stake were central to an orthodox understanding of the trinitarian God. To most modern people, this may seem like a trivial matter, and indeed most ordinary Christians would be hard pressed to explain the doctrine behind this phrase.
