what's the importance of the songs in the story?

Throughout the novel, whenever Kino has a particularly powerful feeling or instinct, he hears a song in his head that corresponds to that feeling. When he is happy with his family in Chapter 1, for instance, he hears the Song of the Family. When he senses malice or dishonesty, he hears the Song of Evil. These songs point to the oral nature of Kino’s cultural tradition. The ancient, familiar songs, presumably handed down from generation to generation, occupy such a central place in how Kino’s people perceive themselves that the songs actually give form to their inner feelings. Kino is much less likely to become aware of the sensation of wariness than he is to hear the Song of Danger in his head. Similarly, he is much less likely to take action because of his own conscious judgment than because he associates the song with a certain kind of urgent behavior in relation to the outside world. The songs also point to Steinbeck’s original conception of The Pearl as a film project; in a motion picture, the songs could be played out loud for the audience to hear and thus function as recurring motifs and melodies that would underscore the story’s themes.