The Vesperae solennes de confessore K. 339 were composed in 1780 for a solemn vespers service in Salzburg Cathedral. Mozart wrote K. 339 on commission from Salzburg Archbishop Hieronymus von Colloredo during his employment as court composer. The Vesperae solennes follow the catholic Vespers liturgy and comprise a total of six movements, including five psalms from the Old Testament and the Magnificat from the Gospel of Luke: "Dixit Dominus" (Psalm 110), “Confitebor tibi Domine” (Psalm 111), “Beatus vir” (Psalm 112), “Laudate pueri Dominum” (Psalm 113), “Laudate Dominum omnes gentes” (Psalm 117) and the “Magnificat” (Luke 1:46-55). The key sequence of the six movements (C-E flat-G-d-F-C) indicates a cycle conceived as a unit. However, the individual psalms can also stand on their own. The soprano aria “Laudate Dominum” is particularly well-known and is often performed individually. It is a heartfelt prayer of a single voice, exuberantly praising the mercy and faithfulness of God.

Alongside the Vesperae de Dominica K. 321 and Mozart's last, unfinished Mass in C minor K. 427, the Vesperae solennes de confessore K. 339 are among the most important sacred works of the 18th century.