To examine any good hero, a good place to start would be to examine their antagonist. In this case, we have Grendel. Grendel, the creature established to be an antithetical foil to Beowulf’s good, was described as a
…. gruesome… cursed creature
(who) lived in a monster’s lair for a time after the Creator had condemned him as one of the seed of Cain – the Everlasting Lord avenged Abel’s murder. (pg 76)
The story of Cain and Abel is well known: Cain killed his brother Abel out of jealousy and anger, thus committing the first murder ever, and then found himself condemned by God for his actions. Original sin goes to Eve, but Cain is the originator of mortal evil in the world.
As one of the descendants of Cain, Grendel was cursed to be alone and live as an outsider, and was thus angered by the merry-making and rabble-rousing occurring at Heorot. The Scyldings decided to seek help.
Strong men often sat in consultation, trying in vain to devise a good plan…
At times they offered sacrifices to the idols in their pagan tabernacles, and prayed aloud to the soul-slayer that he would assist them in their dire distress. Such was the custom and comfort of the heathen; they brooded in their hearts on hellish things –