In the anniversary year of the First Ecumenical Council of Nicaea in 325, it is appropriate for the churches and theology to consider and discuss a whole range of questions and topics that are connected with the creation and transmission of the great creed of Nicaea-Constantinople (NC, 325/381). My remarks today shed light on the relationship of the NC to prayer and the celebration of the Eucharist. For more than a millennium and many centuries, the NC has been encountered by churches, communities and Christians primarily as a prayer in the celebration of the Eucharist. It is prayed in the traditional church languages and in many native languages. The NC is one of the principal pieces of the liturgical heritage. Whether in a Greek or Syrian church tone, whether in Latin Gregorian chant, whether in an orchestral mass by famous composers, whether in an avant-garde setting, the NC is handed down in the guise of song and in its character as a prayer.