Choose, dear Beowulf, the better part,
eternal rewards. Do not give way to pride.
(See Quotations, p. )
Beowulf swims downward for the better part of a day before he sees the bottom. As he nears the murky lake floor, Grendel’s mother senses his approach. She lunges at him and clutches him in her grip, but his armor, as predicted, prevents her from crushing him. She drags Beowulf to her court, while a mass of sea-monsters claws and bites at him. Beowulf wields Hrunting, the sword lent to him by Unferth, and lashes at Grendel’s mother’s head, but even the celebrated blade of Hrunting is unable to pierce the monster’s skin. Beowulf tries to fight the sea-witch using only his bare hands, but she matches him blow for blow. At last, he notices a sword hanging on the wall, an enormous weapon forged for giants. Beowulf seizes the huge sword and swings it in a powerful arc. The blade slices cleanly through the Grendel’s mother’s neck, and she falls dead to the floor, gushing with blood. The hero is exultant. A light appears, and Beowulf looks around, his sword held high in readiness. He spies Grendel's corpse lying in a corner. Furious at the sight of the fiend, he decapitates Grendel as a final repayment for all of the lives that Grendel took.
On land, the Danes lose hope when they see blood well up from the depths. Sure that their champion is lost, they return to Heorot in sorrow. Only the small band of Geats, Beowulf’s kinsmen, waits on.
Back in the monster’s court, the blade of the giant’s sword begins to melt, burned by Grendel’s fiery blood. Beowulf seizes its hilt, which remains solid and, grasping Grendel’s head in his other hand, swims for the surface. He finds that the waters he passes through are no longer infested now that the demon has been destroyed. When he breaks the surface, the Geats are overjoyed as they advance to meet him and unfasten his armor.
The group returns to Heorot in triumph. Four men impale the heavy head of Grendel on a spear and lug it between them. When they arrive at the hall, the Danes gawk at the head in horror and amazement. Beowulf presents the head and the sword hilt to Hrothgar, assuring him of his future security. Hrothgar praises Beowulf’s goodness, evenness, and loyalty, contrasts him with the evil King Heremod, and predicts a great future for him. He delivers a long speech about how to be a good and wise ruler by choosing eternal rather than earthly rewards. Hrothgar then promises to shower Beowulf with treasure the following morning.
Another banquet ensues, with great feasting and revelry. Afterward, Beowulf retires to get some much-needed rest. In the morning, he has Hrunting returned to Unferth and tells Hrothgar that he and his men long to return home to Geatland. Hrothgar praises Beowulf again, saying that he has united the Geats and the Danes in ties of friendship and loyalty. He presents Beowulf with twelve treasures. Despite his urgings that Beowulf return to Denmark soon, Hrothgar knows that he will never see Beowulf again. The Geats return to the coast, where they grant a reward to the watchman who has guarded their ship. They then sail back to Geatland and return to the hall of Hygelac.
Many readers have pondered the significance of Grendel and his mother—whether they are part of the same evil force or represent two separate ideas. Earlier, after Grendel’s defeat, there are frequent suggestions, even amid the celebration, that the evil that Grendel represents has not been stamped out. These hints may lead the reader to suspect that Grendel himself is still alive—though Beowulf rips his arm off, we never actually see Grendel die, and Beowulf regrets letting him get away. That the remaining threat proves instead to be the monster’s mother suggests, perhaps, that although an instance of evil has been eliminated with Grendel, the evil must still be eradicated at its source—Grendel’s mother might be thought of as representing a more foundational or primordial evil than Grendel himself. On the other hand, there is less theological language attached to her malice than to Grendel’s. She seems to be more unambiguously animalistic and less a symbol of pure evil than he is. For example, her attack on Heorot is even appropriate and honorable by the standards of the warrior culture, as it marks an attempt to avenge her son’s death.
This second encounter prompts a change of scene in the poem, drawing the hero out of the safety of the mead-hall and into the dark, alien, suggestive world of his adversaries. The advantage of fighting on familiar terrain within the boundaries of human society—an advantage that Beowulf enjoys in his encounter against Grendel—is now lost. This time, Beowulf must struggle against a resistant natural environment in addition to a ferocious monster. The reader already has been prepared for Beowulf’s superhuman swimming abilities by the earlier story of the contest with Breca. However, the mere, or lake, in which Grendel’s mother lives is no ordinary body of water. It teems with blood and gore, as well as with unsavory creatures of all descriptions. It is an elemental world of water, fire, and blood, and one with an extremely unholy feel to it.
Imagery of darkness and light is important in this underwater world. The darkness of the lair symbolizes evil, and it leads to Beowulf’s general disorientation in this unfamiliar environment. The first glimmer of light that he sees signifies his arrival at the very heart and hearth of this den of terror. Once he defeats Grendel’s mother, her lair is illuminated more thoroughly: “A light appeared and the place brightened / the way the sky does when heaven’s candle / is shining clearly” (1570–1572). Because light bears the implication of Christian holiness and salvation, with these words, the poet suggests that hell has been purged of its evil and sanctity restored. Additionally, it seems clear that by the time Beowulf gets back onto land, he has undergone a sort of rebirth, a transition from a brave but somewhat reckless warrior into a wise and steadfast leader. Indeed, the remainder of this section is dominated by elaborate formal oratory detailing the characteristics of successful participation in society. In particular, Beowulf receives earnest advice from Hrothgar, by now a father-figure, about how to comport himself both as a man and as a ruler.