what is Grendels lineage? what do the characters in the poem know about Grendel? How.is it different from what we know?

Grendel is defended from Cain in the Old Testament. Cain killed his brother able which angered God. It was the original sin. Grendel traces Cain's wickedness in his lineage. The characters only know that Grendel is a nasty monster that has a nastier mother. I don't think they see his tragic side, a displaced monster doomed to live in a swamp and listen to the stories of man.