Sir Gawain has a reputation as "the man to whom all excellence and valour belongs, / Whose refined manners are everywhere praised" (911-912). In other words, he’s both a really great knight and a master of courtoisie (courtesy). When the narrator describes the pentagram on Gawain’s shield, he explains to us that the five sides of the pentagram represent the five areas in which Gawain excels:
To maintain his reputation as an excellent knight, Gawain must remain loyal to his lord at all times, always fulfill his promises, and display skill and bravery with a weapon. As a master of courtoisie, he must delight everyone with his conversational skills and, in particular, treat ladies with worshipful respect. These two sides of Gawain’s character come into conflict when the lady of the castle attempts to seduce him. Gawain is faced with the conundrum of how to reject her advances politely so that he can remain a good knight (since good knights don’t generally have affairs with other men’s wives).
In the course of Sir Gawain and the Green Knight, Gawain’s character undergoes testing not only during the seduction scenes, but also as his survival instinct wars with his knightly duty to fulfill his oath to the Green Knight. This survival instinct causes Gawain to slip at the end of the story; he fails to turn over the green girdle to Lord Bertilak as the rules of their exchange-of-winnings game (and of knightly conduct) dictate. Yet, as Lord Bertilak reminds Gawain, in this, he’s only human. Finding that out, however, is difficult for Gawain, who berates himself as a failure. Like most medieval romance heroes, Gawain’s adventure ends up teaching him a lot about himself – in this case, that he’s not perfect, no matter what anybody says and how hard he might try to be.
In the symbolic scheme of Sir Gawain and the Green Knight, which emphasizes the contrast between civilization and the natural world outside of it, Gawain is the character perhaps most closely connected to civilization. This is because of his adherence to not one but three of civilization’s ordering systems – chivalry, courtoisie, and Christianity.
Yet even this most civilized character has a bit of the animal within him. The poem’s structure, which places scenes of hunting next to those of Gawain’s seduction, encourages us to compare Gawain to the animals Bertilak hunts. And at the end of the poem, when Gawain gives into his survival instinct, he learns that at least a small part of the animal still resides within him. Like the Green Knight / Bertilak, Gawain’s character incorporates both the wild and the civilized into one person. Unlike the Green Knight, however, Gawain only comes to this realization at the end of the tale, allowing the reader to share in his revelation in the process.