motif began to appear, again in a series of drawings, some incorporating dried vegetable pigments: a mysterious patch of light cast by an unseen window that serves as background for phrases such as WONDER SICKNESS and 99% DEVIL, 1% ANGEL. By the 1990s, Ruscha was creating larger paintings of light projected into empty rooms, some with ironical titles such as An Exhibition of Gasoline Powered Engines (1993).

Born and raised Catholic, Ruscha readily admits to the influence of religion in his work. He is also aware of the centuries-old tradition of religious imagery in which light beams have been used to represent divine presence. But his work makes no claims for a particular moral position or spiritual attitude.