What does Lorenzo say about divine music?

The answer to your question lies in act 5, scene 1.
Jessica and Lorenzo talk while the music plays. During the conversation, Lorenzo tells Jessica that divine music is everywhere, from the smallest planets moving in harmony to the immortal souls of human beings. However, Lorenzo asserts that we are insensible to this divine music: our immortal souls are enclosed by our mortal bodies ("muddy vesture of decay"), and "we cannot hear it."
Lorenzo goes on to describe the power of beautiful or divine music. Such music is so compelling that it will tame even the most "wild and wanton herd." He claims that the "sweet power of music" will turn the "savage eyes" of these animals to a "modest gaze." Lorenzo is convinced that there are none so "stockish, hard, and full of rage, / But music for the time doth change his nature."
Lorenzo believes that beautiful music can be a positive influence on one's mood and behavior. He maintains that a man who cannot be moved by the "concord of sweet sounds" should not be trusted: he is only good for "treasons, stratagems, and spoils."