1 Samuel 16:21-23

21When David came to Saul and entered his service, Saul loved him very much, and David became his armor-bearer.

22Then Saul sent word to Jesse, saying, “Let David remain in my service, for I am pleased with him.” 23And whenever the spirit from God came upon Saul, David would pick up his harp and play. Then Saul would find relief and feel better, and the spirit of distress would depart from him.