The hymn on which the mass is based is the famous "Pange Lingua Gloriosi", by Thomas Aquinas, which is used for the Vespers of Corpus Christi, and which is also sung during the veneration of the Blessed Sacrament. The mass is the last of only four that Josquin based on plainsong (the others are the "Missa Gaudeamus", a relatively early work, the "Missa Ave maris stella", and the "Missa de Beata Virgine"; all of them involve, in some way, praise of the Virgin Mary). The hymn, in the Phrygian mode, is in six musical phrases, of 10, 10, 8, 8, 8, and 9 notes respectively, corresponding to the six lines of the hymn. The work is tightly organized, with almost all of the melodic material drawn from the source hymn, and from a few subsidiary motifs which appear near the beginning of the mass. As such, the "Missa Pange lingua" is considered to be one of the finest examples of a paraphrase mass.