After the formulation of the Nicene Creed, its initial liturgical use was in baptism, which explains why the text uses the singular "I ... instead of "we...." The text was gradually incorporated into the liturgies, first in the east and in Spain, and gradually into the north, from the sixth to the ninth century. In 1014 it was accepted by the Church of Rome as a legitimate part of the service. It is recited in the Western Mass directly after the homily on all Sundays and Solemnities (Tridentine Feasts of the First Class), and in the Eastern Liturgy following the Litany of Supplication on all occasions.
Probably because of its late adoption, and the length of the text (the longest in the Ordinary of the Mass), there are relatively few chant settings of it. What is identified as "Credo I" in the Liber Usualis was apparently widely considered the only authentic credo, and it is the element of the ordinary that was most strongly associated with a single melody. The Liber Usualis contains only two other settings, designated as "Credo V" and "Credo VI," which is far fewer than for other settings of the Ordinary.
In musical settings of the credo, as in the Gloria, the first line is intoned by the celebrant alone ("Credo in unum Deum"), or by a soloist, while the choir or congregation joins in with the second line. This tradition continued through the Middle Ages and Renaissance, and is even followed in more recent settings. In Stravinsky's Mass, for example, a soloist intones the first line, which is from the plainchant Credo I. In mass settings of the Classical and Romantic period (for example the later masses of Haydn, and the Missa Solemnis of Beethoven) the Credo line is usually set for whole choir.
The melody of Credo I first appears in eleventh-century manuscripts, but it is believed to be much older, and perhaps Greek in origin. It is almost entirely syllabic, probably because of the length of the text, and consists of a great deal of repetition of melodic formulas.
In polyphonic settings of the Mass, the Credo is usually the longest movement, but is usually set more homophonically than other movements, probably because the length of the text demanded a more syllabic approach, as was seen with chant as well. A few composers (notably Heinrich Isaac) have set Credos independently from the rest of the ordinary, presumably to allow their insertion into missae breves or their omission where a said or chanted credo is the custom.
- This is the original Latin text used in chants and most modern settings of the Mass. For translations, see Nicene Creed.
Credo in unum Deum, Patrem omnipoténtem, factórem cæli et terræ, visibílium ómnium et invisibílium;
Et in unum Dóminum Iesum Christum, Fílium Dei unigénitum, et ex Patre natum ante ómnia sæcula: Deum de Deo, lumen de lúmine, Deum verum de Deo vero, génitum non factum, consubstantiálem Patri, per quem ómnia facta sunt; qui propter nos hómines et propter nostram salútem descéndit de cælis; et incarnátus est de Spíritu Sancto ex María Vírgine et homo factus est; crucifíxus étiam pro nobis sub Póntio Piláto, passus et sepúltus est; et resurréxit tértia die secúndum Scriptúras; et ascéndit in cælum, sedet ad déxteram Patris; et íterum ventúrus est cum glória iudicáre vivos et mórtuos; cuius regni non erit finis;
Et in Spíritum Sanctum, Dóminum et vivificántem: qui ex Patre Filióque procédit; qui cum Patre et Fílio simul adorátur et conglorificátur; qui locútus est per Prophétas;
Et unam sanctam cathólicam et apostólicam Ecclésiam.
Confíteor unum baptísma in remissiónem peccatorum; et expecto resurrectionem mortuorum et vitam ventúri sæculi. Amen.
- Hoppin, Richard. Medieval Music. New York: Norton, 1978. Pages 136-138.