The epic of Beowulf contains many symbolic characters and places. The symbolic characters are Beowulf, Grendel and his mother, Hrothgar, and Unferth. The symbolic places are Heorot and Grendel's mother's lair.
Beowulf, as the epic hero, symbolizes all of the characteristics the Anglo-Saxon culture desired (courage, strength, generosity, desire for fame) in their heroes. His actions speak loudly to his true heroic nature (possession of aristeia (nobility in battle) and arete (excellence)). He proves that actions speak louder than words and to never make a promise (or battle boast) one cannot keep.
Grendel and his mother symbolize the dark side of life (those outside of God's love). Since their exile, both have been forced to live in darkness. Forbidden to live in the light (God's light), both symbolize the evil (of good verses evil).
Hrothgar, the king of the Danes, symbolizes the elder who possesses the knowledge others need in order to succeed as men, heroes, and kings. Hrothgar passes on much excellent information and advice to Beowulf.
Unferth symbolizes the idea that one cannot only "talk the talk." Instead, all men must "walk the walk." The challenge by Unferth against Beowulf proves to be important given Unferth's change of heart later in the epic.
Heorot symbolizes the power of God. Hrothgar builds Heorot in order to thank God for all of his successes in battle. The mead hall is also used to celebrate all God has done for the Danes. Given the association of Heorot with God and light, Grendel is unable to approach the throne of God (within the hall).
Grendel's mother's lair symbolizes the underworld. As part of an epic hero's journey, the epic hero must take on a long journey. This journey typically includes a descent into the underworld. In Beowulf, Grendel's mother's lair symbolizes the underworld (hell).