How did Beowulf become an epic hero in Beowulf ?

was born to
be extraordinary.  His early
heroic deed involved setting off into the sea with a friend and
being the
only one coming back alive.  He proved more might in the sea than any other man,
and
more endurance in the ocean (ch 8, p. 14) when he outswam his friend and
fought off the
sea-fish.  An epic hero usually does have an early deed that
shows his ability to accomplish an
amazing feat.

Of
course, it was Beowulfs defeat of Grendel that cemented him
as the epic
hero.

His sinews ripped apart and his

bone-frame broke. victory was now given to Beowulf, and Grendel, sick unto his death,
went hence
and sought his den in the dark moors, that vile abode; he knew
full well that his life had
reached its end and that the last of his days on
earth had come. (Ch 12, p. 18)

Beowulf
is able to kill Grendel with his bare hands and brute
strength, and his
exploits are sung in praise throughout the kingdoms.