Sanctus

The fourth chant of the Ordinary of the Roman Mass. Its text is founded on the book of Isaiah (vi. 3) and Matthew's gospel (xxi. 9) and it was incorporated into the Latin liturgy as early as the 6th century in Gaul.

The Sanctus was set in polyphony from the 13th century, and became an integral part of all settings of the Ordinary of the Mass. Later settings are more complex: a total of 231 melodies were catalogued in 1962. The earliest known melody is that of Mass XVIII (Vatican edition).

The chant is basically syllabic, forms a natural continuation from the music of the Preface which precedes it, is psalmodic in structure, and its last phrase echoes the Per omnia saecula saeculorum formula which occurs three times during the Preface and Canon of the Mass.