Final answer:
Gawain upholds his part of the bargain by meeting the Green Knight, but violates the values of the Pentangle by concealing the girdle he received. He is spared but learns from his mistake, wearing the girdle as a reminder of his lapse in integrity.
Step-by-step explanation:
In Sir Gawain and the Green Knight, particularly in Part 4, we reach the resolution of Gawain's quest and his moral trial. Gawain does indeed uphold his part of the bargain to seek out the Green Knight a year after their initial meeting in Arthur's court. When he finally confronts the Green Knight at the Green Chapel, he presents himself bravely, ready to receive the returning blow as agreed. However, Gawain does not fully uphold the values of the Pentangle that he carries on his shield, which stands for the five knightly virtues of generosity, courtesy, chastity, chivalry, and piety.
Gawain accepts a girdle from the lord's wife as a talisman to protect his life, which he fails to disclose to the lord although they had a pact to exchange whatever they gained during the day. This act of concealment breaches the values of the Pentangle, more specifically reflecting a lapse in courtesy and integrity. Despite this, the Green Knight, who is revealed to be the lord in disguise, spares Gawain, administering only a nick to his neck as a token punishment for his deceit. Gawain is ashamed of his action and adopts the girdle as a symbol of his failure to adhere to his code of honor.