The filioque clause affirms that the Spirit eternally ‘proceeds from the Father and the Son’, countering the subordination of the Son with a demonstration of his coequality with the Father. From its affirmation by the Canons of the Council of Toledo in AD 589, its inclusion in the Niceno-Constantinopolitan Creed became increasingly widespread throughout Europe; it was adopted into Roman Use by Benedict VIII in the eleventh century. This became a principal factor in the schism with the Church in the East, which alleges that, by seeming to deny that the Father is the sole principle and cause of the Son and the Spirit, the filioque threatens the unity of God and the distinction between the Father and the Son.1Anonymous, ‘The filioque clause in ecumenical perspective,’ in Spirit of God, Spirit of Christ (ed. L Vischer; London: SPCK, 1981), pp. 4–6, 13.
There has been an ecumenically-motivated renewal of attention to the filioque in the West, leading some to propose new mediating formulations