This is an original lithograph in colours by Marc Chagall titled "David and his Harp".
It was printed in 1956 as part of the series "The Bible" in a limited but unsigned edition.
The work bears an additional black and white lithograph on the reverse, see images.
The series was printed by Mourlot, Paris and published by editions Verve.
Literature: Mourlot, Fernand, and Sorlier, Charles, 1998. Chagall: The Lithographs (Catalogue Raisonne). D.A.P./Distributed Art Publishers, Inc.
Reference: Mourlot 134 & Mourlot 137