Divine Harmony and the Discordant Soul
It matters what we sing.
Saul has driven away the Spirit of the Lord by his repeated rejection of God's word. An evil spirit from the Lord is terrorizing him. Saul's condition is known to Saul; it is known to Samuel; and it is known to everyone in Saul's court.
The search for a skilled harpist commences in hopes that the music will bring relief to Saul's mental state. The search ends with "the sweet psalmist of Israel," the shepherd boy David, who is a cunning player on the harp.
What does David play? What should be the theme of the music we listen to when we are feeling overwhelmed and in despair?