what is the simbolic significance of the Beheading game and the Exchange Game in 'Sir Gawain and the Green Knight'?

Your question has to do with the The Nature of Chivalry. The world of Sir Gawain and the Green Knight is governed by well-defined codes of behavior. The code of chivalry, in particular, shapes the values and actions of Sir Gawain and other characters in the poem. The ideals of chivalry derive from the Christian concept of morality, and the proponents of chivalry seek to promote spiritual ideals in a spiritually fallen world.

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