When Grendel says "warriors became hornets" (40), what literary device is being used?

When Grendel says "I cannot bear the joy in this hall," he is expressing his envy and hatred of the Danes' happiness. He cannot stand the sound of their laughter and music, and he is infuriated by their feasting and merriment. Grendel is a solitary creature who lives in the darkness, and he cannot understand or appreciate the joy of human companionship. He sees the Danes as happy and carefree, while he is miserable and alone. This makes him even more determined to destroy them.