If the Dane could fight as well as he talks, says Beowulf, King Hrothgar might not have such a problem with Grendel. Unferth later admits Beowulf's superiority after the defeat of Grendel and lends him a treasured sword, Hrunting, for the battle with Grendel's mother. While the sword is ineffective, at least the Dane is making an effort.
Unferth's challenge to Beowulf—implying that Beowulf has been defeated by his friend Breca—is important because it allows Beowulf to establish his credentials by telling his side of the Breca story, which enhances his stature in the eyes of the Danes. Just as physical strength is honored in this culture.
Unferth’s challenge to Beowulf’s honor differentiates him from Beowulf and helps to reveal some of the subtleties of the heroic code that the warriors must follow. Unferth is presented as a lesser man, a foil for the near-perfect Beowulf. (A foil is a character whose traits contrast with and thereby accentuate those of another character.).
Unferth's slur accuses Beowulf of foolishly engaging in a seven-day swimming contest on the open sea, as a youth, and losing. If Beowulf can't win a match like that, Unferth asserts, he surely can't defeat Grendel. Beowulf defends his reputation with such grace and persuasion that he wins the confidence of King Hrothgar and the rest of the Danes.
Unferth’s Challenge. When Beowulf arrives at Heorot Hall to help the Danes, there is a celebration in the warrior’s honor, and the men talk of Beowulf’s heroic feats. But not everyone is happy to see him. In fact, Unferth is jealous of Beowulf’s celebrated reputation and probably a little embarrassed that he can’t defeat Grendel himself.
But Unferth and Beowulf are the ones who influence Grendel 's reason to become the monster of the Danes. Theses two who would spend their lives trying to become great heroes so that their names will live on forever. Heroism is as an act of great bravery regardless of the outcome, for one reason; the intention behind the act.
Swimming Contest with Breca. voice came from the mead-benches. Unferth, son of Eglaf, spoke. Unferth was a well-known warrior, an important man among the Danes. He could not bear to think that anyone was braver or could do more famous deeds than he. 'Aren't you the Beowulf who had the swimming contest with Breca?' Unferth asked.
A Dane, the son of Ecglaf, and a follower of Hrothgar.Unferth is presented as contrast to Beowulf, providing a glimpse of a poor warrior in contrast to Beowulf's good warrior.Unferth is boastful, just as Beowulf is, but unlike Beowulf Unferth lacks the moral courage to back up his boasts (and unlike Beowulf Unferth never does anything to stand against Grendel).
Unferth was one of the Danish warriors and he had some jealousy features that he showed when trying to challenge Beowulf’s honor. He proved that he was non-daring and inferior to Beowulf by being unwilling and unable to take on Grendel. In fact, the challenge of Unferth to Beowulf honor differentiated him from the little renowned hero, Beowulf.