The opening passages of Sir Gawain and the Green Knight frame the tale as a "marvellous event," a "prodigious happening among tales about Arthur" (28, 29). As we read the poem, we begin to understand more fully what comprises the wondrous or marvelous in its world. As Arthur’s court contends with the wonder of the entirely green man who picks up his own severed head and speaks with it, they are rendered entirely passive and speechless. They are unable to proceed when faced with such an unfamiliar situation. When the Green Knight leaves the court, Arthur is relieved, but also aware that he has gotten what he desired - to witness a wonder.
Arthur's reaction captures the feelings of joy and turmoil that wonder brings in its wake. Characters are simultaneously elated and shocked by what’s new and unfamiliar. This feeling of wonder might also describe our encounter with the poem. We share in characters’ awe at the marvelous happenings while simultaneously experiencing their discomfort and sorrow.
Sir Gawain and the Green Knight shows how joy and turmoil are both equal parts of wonder.
Wonder robs characters of their ability to speak and act in Sir Gawain and the Green Knight, because it confronts them with a situation with which they are entirely unfamiliar