In the novel, "The Great Gatsby," the eyes on the billboard of a certain oculist named Dr. T.J. Eckleburg symbolize the eye of God that sees everything. The eye shows that even when people think that they are successful in hiding their misdeeds, they cannot hide it from God.
The billboard of Dr. Eckleburg figures in passing in the early part of the novel. It was mentioned to be watching over the garage of the Myrtle and her husband, George Wilson. Later in the novel, George made reference to the billboard when he accused Myrtle of having an affair with Tom Buchanan, saying that God sees everything. Finally, the billboard was in the backdrop in the pivotal part of the novel when Daisy, who is Tom's wife, hit Myrtle with a car, killing her.