Was surprised to hear that Lutherans recite the Athanasian creed, also known as Quicunque Vult or Fides Catholica, during their liturgy on Trinity Sunday. St. Athanasius most likely did not compose this creed himself. I had never even heard of this creed until recently after listening to stories about St. Athanasius, bishop of Alexandria, on the EPIC CDs and then reading a little on the saint myself. For me, with my Irish heritage, Trinity Sunday always reminds me of St. Patrick and the clover leaf.
St. Athanasius defended the Church's doctrine on the Trinity against Arianism. "God was not always Father" was how the heresy was summed up on EPIC.
It would be nice if our friends would come home to Rome instead of borrowing creeds, the Bible, etc!
Background on the Athanasian Creed from Wiki is below. The link also contains the text of the creed:
Composed of 44 rhythmic lines, the Athanasian Creed appears to have been intended as a liturgical document - that is, the original purpose of the creed was to be spoken or sung as a part of worship. The creed itself uses the language of public worship, speaking of the worship of God rather than the language of belief ("Now this is the catholic faith: We worship one God"). Among medieval European Christian churches, this creed was recited following the Sunday sermon or at the Sunday Office of Prime. The creed was often set to music and used in the place of a Psalm.
Early Protestants inherited the late medieval devotion to the Athanasian Creed, and it was considered to be authoritative in many Protestant churches. The statements of Protestant belief (confessional documents) of various Reformers commend the Athanasian Creed to their followers, including the Augsburg Confession, the Formula of Concord, the Second Helvetic Confession, the Belgic Confession, the Bohemian Confession and the Thirty-nine Articles. Among modern Lutheran and Reformed churches adherence to the Athanasian Creed is prescribed by the earlier confessional documents, but the creed does not receive much attention outside of occasional use - especially on Trinity Sunday.
In Reformed circles, it is included (for example) in the Christian Reformed Churches of Australia's Book of Forms (publ. 1991). That said, it is rarely recited in public worship.
In the successive Books of Common Prayer of the reformed Church of England from 1549 to 1662, its recitation was provided for on 19 occasions each year, a practice which continued until the nineteenth century, when vigorous controversy regarding its statement about 'eternal damnation' saw its use gradually decline. It remains one of the three Creeds approved in the Thirty-Nine Articles, and is printed in several current Anglican prayer books (e.g. A Prayer Book for Australia (1995)). As with Roman Catholic practice, its use is now generally only on Trinity Sunday or its octave.
In Roman Catholic churches, it was traditionally said at Prime on Sundays after Epiphany and Pentecost, except when a Double feast or day within an octave occurred, and on Trinity Sunday. In the 1960 reforms, it was reduced to once a year on Trinity Sunday. It has been effectively dropped from the Catholic liturgy since Vatican II, although it is retained in the Anglican Book of Common Prayer. It is however maintained in the Forma Extraordinaria, per the decree Summorum Pontificum, and also in the rite of exorcism, both in the Forma Ordinaria and the Forma Extraordinaria of the Roman Rite.
In Lutheranism, the Athanasian Creed is—along with the Apostles' and Nicene Creeds—one of the three ecumenical creeds placed at the beginning of the 1580 Book of Concord, the historic collection of authoritative doctrinal statements (confessions) of the Lutheran church. It is still used in the liturgy on Trinity Sunday.