How does the writer use conflict and comparison and contrast of Beowulf and Unferth to develop or support meaning/theme?

These themes stated, the most universal is good verses evil. Unferth is presented as contrast to Beowulf, providing a glimpse of a poor warrior in contrast to Beowulf's good warrior ... Unferth does become more generous after Beowulf defeats Grendel, and lends Beowulf his family sword to fight Grendel's mother.