Magennis emphasizes that treachery exists within groups as well as between them.
Unferth killed his own brother, and the Danes not only tolerate this, but even give him a place of honor in the hall, sitting at Hrothgar’s feet.
Heremond, a bloodthirsty former king who turned on his companions, is alluded to.
Hrothulf eventually betrays Hrothgar.
The Geats fail Beowulf in the end.
Beowulf accepts the shortcomings of others and tries to do his best; it is a grim fact that people disappoint. He doesn’t expect too much of them.
notes from Hugh Magennis, Images of Community in Old English Poetry, 1996