'Jonas' and 'Dives Malus' are particularly showy examples of the "sacred oratorios" with Latin texts chiefly taken from the Bible, which were extremely popular among the Italian aristocracy, both secular and clerical, throughout the 17th Century. Such musical theater pieces were the Counter-reformation's answer to the opera and secular oratorio, usually based on tales from Graeco-Roman sources, beloved of the Humanists. If any difference in the music is to be heard, it is that the sacred oratorios are more purely aesthetic and intellectual, while the secular oratorio is more easily comprehended by the untrained listener.
The oratorios of the 17th century Italian composer Giacomo Carissimi, though distant ancestors of the familiar works of Haydn and Mozart, are quite different in scope and effect. They were church works, for one thing; the Latin oratorios recorded here were composed for Lenten celebrations in a Roman church, for literate worshippers who would have known the texts well and would have been attuned to what the composer was doing with them. Perhaps a good place for the modern listener to start is with the opening Jonas, which recounts the tale of Jonah's placement in belly of the whale and has as its climax his extended intra-cetaceian prayer.