How did parody masses borrow material from earlier motets, hymns, or secular pieces?

A parody mass is a 16th-century musical form in which a composer creates a new setting of the Ordinary of the mass by borrowing and reworking musical material from an existing composition, such as a motet, hymn, or secular work like a chanson or madrigal.123

Unlike earlier techniques that might rely on a single cantus firmus (a pre-existing melody), the parody technique involves the creative reworking of multiple voice parts from the model composition. Composers would freely reorganize and expand upon this borrowed material, often inserting new sections between the modified passages to integrate the borrowed themes into the new liturgical context.23

This method allowed composers to base an extended work on the recognizable material of a shorter piece, providing a foundation that could gradually transition into inventive, independent musical development. The resulting mass was typically identified by the name of the model work, such as Josquin des Prez's Missa Malheur me bat, which reworks a chanson by Jean d'Okeghem.42