Unferth and Grendel
Could Grendel be a scourge of God, sent to punish the Danes because they harbour a fratricide, Unferth, in their midst? The idea has been put forward, but I do not believe it is that simple. The poem is too full of stories about feuds that have an only too human ending: no monsters involved.
Unferth does have a dark side, though. The story I’ve attached is just one take on what this dark side may be. Just a play with ideas.

Grendel couldn’t be a scourge sent by God. In “Beowulf,” it states that he he wasn’t able to touch the throne in Herot since God wouldn’t let him. And he was there before the Danes were. If he was sent to punish the Danes, he would have been sent after the Danes appear.
Grendel is nothing less than a scourge of god. Through reading Beowulf we are forced to believe that Grendel himself is the monster. While reading Grendel, I also put the connection together that Grendel is not the punished but the punisher. His purpose is to correct the Danes.
Grendel’s situations has nothing to do with Unferth. Unferth serves as Beowulf’s foil in this epic poem. His envious nature contrast with Beowulf’s heroic persona. In Beowulf, Grendel’s represented as a mindless, motiveless terrorizer, however the story of Grendel states otherwise. Grendel’s terrorism is his attempt at reverting society back to it’s pure nature before the creation of the mead hall corrupted the citizen’s of Hart. The connection between Grendel an Unferth cannot be accounted for.