In the tale of Beowulf, the monster Grendel is said to be descended from the biblical character of Cain. This was surprising to me, as I'd thought Beowulf was a pre-Christian story given its setting in pagan Germanic countries, but I learned that paganism vs Christianity in Beowulf is a hotly debated subject, so I won't go into that large topic here. Instead, my question is simple: what is the significance of Grendel being descended from Cain? Does his ancestry have any bearing on the character of Grendel, or is there any parallel between his story and Cain's? Why does the story mention Cain as an ancestor of Grendel?