What is the significance of the digressions in the Anglo-Saxon poem Beowulf?
Beowulf includes several digressions--Unferth's challenge to Beowulf, the fight at Finnsburg, Hrothulf's treachery, among others--that are designed either to enhance Beowulf's stature as the poem's hero or to remind the listener's of important events in their history. Because the culture to which the poem is addressed is an oral culture, the poet uses digressions not only to remind listeners of important historical events but also, through the act of recounting these events in this poem, interpret this shared history.
One of the most important digressions early in the poem in Unferth's challenge to Beowulf:
Are you that Beowulf/who with Breca strove,/on the open sea/over a swimming match,/where you two out of pride/tempted the floods/for this doltish boasting. . . . (ll. 506-509)
Unferth's purpose in this digression is both to challenge Beowulf's physical strength and his common sense, essentially accusing Beowulf of stupidity in choosing to waste his strength and, more important, to point out that Breca came ashore first--implying that Breca was the winner of this swimming contest. Unferth concludes this challenge by saying that Beowulf, just as he failed in the swimming contest, will fail in his struggle with Grendel.
Beowulf's version, however, is significantly different from Unferth's: Beowulf recounts several battles with sea serpents during the contest--battles that Beowulf won--and points out that "Breca never yet . . . performed such a deed with drawn sword." Beowulf concludes this digression by pointing out that neither Breca nor Unferth performed such heroic deeds with swords "although you were your brother's killer,/your close kinsman." (ll.587-88) This digression performed two purposes--it recounts an instance of Beowulf's physical prowess, and it brands Unferth as the killer of his own brother and therefore unworthy to challenge Beowulf's credibility.
Another similar digression occurs with the mention of Sigemund and Fitela at lines 875-900. One of Hrothgar's retainers recounts the story of Sigemund in which Sigemund
. . . killed, after a struggle,/a strong worm-dragon,/a hoard's keeper. He, the prince's son,/under a hoary stone ventured alone,/a fearless deed. . . the dragon died of that wound. . . . (ll. 885-892)
Clearly, this digression would have resonated with the audience of Beowulf because Sigemund's tale, in large part, is very similar to Beowulf's last battle with the dragon whose hoard has been violated. The digression, then, connects Beowulf directly to Sigemund, whose reputation would have been widely known and highly regarded by the audience of Beowulf.