The present volume contains the Psalmi Davidis Poenitentiales, seven penitential psalms that had already been supplemented with the motet Laudate Dominum de coelis in the first edition (1584). In the Complete Edition, however, the compilation is preceded by the vocal piece S u Su p e r per Super (1567), which experiments with syllables. Though reprinted many times, it was assigned to various genres according to its place of publication: while the piece was considered as a motet in Germany, in France it was classified as a chanson and in Italy as a madrigal – a unique case in the reception history of vocal music in the 16th century. To this day we still do not know the significance of the vocal text Super flumina Babylonis, which gradually evolves out of syllables. Perhaps Lasso wanted to depict a biblical scene that evokes the gradual learning of a language.