[The opening scene of The Seventh Seal] is not merely a piece of cinematic exposition; it is a thematic prelude: in the image of the gliding bird seen against a sky which is "a dome of lead," Bergman telescopes the knight's hopeless search for God, who remains distant and silent. (p. 92)

Although the knight's quest is medieval, his skeptic and anxious temper is modern. To help justify such an anachronism Bergman claims that the medieval world depicted in The Seventh Seal is basically a historical metaphor for our own world threatened by atomic destruction: "In my film the Crusader returns from the Crusades as the soldier returns from the war today. In the Middle Ages, men lived in terror of the plague. Today they live in fear of the atomic bomb. The Seventh Seal is an allegory with a theme that is quite simple: man, his eternal search...