Wellcome Library contributed this etching by Willem van der Leeuw (1603-1665) after Rembrandt from their collection on Twitter on Jan. 24, 2019, with this caption:
The boy David playing the harp before Saul. Saul is mentally ill (“mala mens et amara Sauli est”): the music soothes his disturbed mind.
More affirmation for choosing the harp as the logo for HARP Publishing, The People’s Press www.harppublishing.ca