Then a fierce evil demon suffered distress, long in torment, who dwelt in darkness. For day after day, he heard rejoicing loud in the hall: there was music of the harp, and the clear song of the scop, who sang of creation, the beginnings of men far back in time.
The poet introduces Grendel, the monster, by picturing him as distressed and tormented by the rejoicing he hears in the hall. The music being played is a song of creation, in praise of God. Such music brings pain to Grendel because he is a demon. Grendel represents evil, so the poet’s Christian worldview turns him into a fiend from hell.
The wicked creature, grim and greedy, was at the ready, savage and cruel, and seized in their rest thirty of the thanes.
The poet describes Grendel’s first attack on Hrothgar’s men. The monster is strong enough to seize thirty unsuspecting warriors, who are sleeping peacefully. After this first attack, the warriors will suffer many sleepless nights as Grendel’s cruel attacks increase and as Hrothgar grows weaker.
The dreaded demon suffered terrible torture, as his shoulder tore open, a great wound gaping as sinews sprang apart, and the bone-locks burst. To Beowulf then was glory given in battle.
The poet describes the moment when Grendel has his arm torn out by Beowulf. The poet added details to help the audience feel the monster’s pain. The monster will soon flee the hall, leaving his arm behind, and crawl home to die. The poet does not describe Grendel’s actual death—a strong clue that the monster will reappear in some form later in the story.
No fewer than four were needed to hold up the head of Grendel On the shaft of a spear, going to the gold-hall…
Beowulf has killed Grendel’s mother, found Grendel’s corpse, and cut off his head, and he now bears the head back to the hall to show Hrothgar. The poet’s description helps the audience picture the immense size of the monster. Grendel’s head is an even more impressive war trophy than his arm.