Credo

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 ...".

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.

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.

Settings of alternative texts as a Credo outside the Mass, as a motet, are extremely rare.