Describe Mr. Gatsby's behavior as he leaves the mansion. How do you explain it?

The first appearance of Gatsby has a religious solemnity, and Gatsby himself seems almost godlike: Nick speculates that Gatsby has "come out to determine what share of our local heavens [was his]." He is utterly alone, a solitary figure in a posture of mysterious worship. When the reader first sees Gatsby, he is reaching toward the green light ­ something that, by definition, he cannot grasp. In this scene, Fitzgerald wholly sacrifices realism in favor of drama and symbol: the green light stands for the as-yet-nameless object for which Gatsby is hopelessly striving.