Beowulf The Supernatural

So times were pleasant for the people there
until finally one, a fiend out of hell,
began to work his evil in the world.
Grendel was the name of this grim demon
haunting the marches, marauding round the heath
and the desolate fens; he had dwelt for a time
in misery among the banished monsters,
Cain's clan, whom the creator had outlawed
and condemned as outcasts. (99-107)

Then a powerful demon, a prowler through the dark,
nursed a hard grievance. It harrowed him
to hear the din of the loud banquet
every day in the hall, the harp being struck
and the clear song of a skilled poet
telling with mastery of man's beginnings. (86-91)

The first adversary in Beowulf is no mere man, but a supernatural demon, angered by the very mention of God's creation. Notice that the supernatural elements in Beowulf are intermingled with the religious ones. Grendel is an ogre-like creature, but also a demon with a part (albeit a negative one) to play in a Christianized world.

All were endangered; young and old
were hunted down by that dark death-shadow
who lurked and swooped in the long nights
on the misty moors; nobody knows
where these reavers from hell roam on their errands. (159-163)

"Time and again, foul things attacked me,
lurking and stalking, but I lashed out,
gave as good as I got with my sword.
My flesh was not for feasting on,
there would be no monsters gnawing and gloating
over their banquet at the bottom of the sea.
Instead, in the morning, mangled and sleeping
the sleep of the sword, they slopped and floated
like the ocean's leavings." (559-567)

When they joined the struggle
there was something they could not have known at the time,
that no blade on earth, no blacksmith's art
could ever damage their demon opponent.
He had conjured the harm from the cutting edge
of every weapon. (799-804)

"I have heard it said by my people in hall,
counsellors who live in the upland country,
that they have seen two such creatures
prowling the moors, huge marauders
from some other world. One of these things,
as far as anyone ever can discern,
looks like a woman; the other, warped
in the shape of a man, moves beyond the pale
bigger than any man, an unnatural birth
called Grendel by country people
in former days. They are fatherless creatures
and their whole ancestry is hidden in a past
of demons and ghosts. (1345-1357)

The water was infested
with all kinds of reptiles. There were writhing sea-dragons
and monsters slouching on slopes by the cliff,
serpents and wild things such as those that often
surface at dawn to roam the sail-road
and doom the voyage. (1425-1430)

Meanwhile the sword
began to wilt into gory icicles,
to slather and thaw. It was a wonderful thing,
the way it all melted as ice melts
when the Father eases the fetters off the frost
and unravels the water-ropes. He who wields power
over time and tide: He is the true Lord. (1605-1611)

That huge cache, gold inherited
from an ancient race, was under a spell –
which meant no one was ever permitted
to enter the ring-hall unless God Himself,
mankind's Keeper, True King of Triumphs,
allowed some person pleasing to Him –
and in His eyes worthy – to open the hoard. (3051-3057)