The relationship between Grendel and Hrothgar is one of hate; Grendel loathes the celebrations of God that take place at Heorot. Though Beowulf and Hrothgar had no personal relationship before Beowulf arrived to slay Grendel, Hrothgar knew Beowulf's father, respected him and believes that Beowulf might be able to help save Heorot.
The narrator in Beowulf describes Grendel as a monster who was cast out from the sight of men. As Hrothgar builds Heorot and the men gather to enjoy their feasts and tales, Grendel stirs. The narrator describes Grendel, saying:
Grendel this monster grim was called,
march-riever mighty, in moorland living,
in fen and fastness; fief of the giants
the hapless wight a while had kept
since the Creator his exile doomed.
On kin of Cain was the killing avenged
by sovran God for slaughtered Abel.
Ill fared his feud, and far was he driven,
for the slaughter’s sake, from sight of men.
Of Cain awoke all that woful breed,
Etins and elves and evil-spirits,
as well as the giants that...
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