Which parts of this passage contain a biblical allusion?

Grendel this monster grim was called,
march-riever mighty,
fief of the giants
the hapless wight a while had kept
On kin of Cain was the killing avenged
by sovran God for slaughtered Abel.
from sight of men. Of Cain awoke all that woful breed,
Etins and elves and evil-spirits,