In this post, I am going to explore Grendel's relation with Cain, and how this affects his gigantism and his monstrosity in general. While I already posted on Grendel and Cain TWO WHOLE YEARS AGO HOLY SHIT (existential crisis), that post was more focused on the Book of Enoch and antediluvian aspects of the Cain legend.
|The lads as depicted in the Speculum Humanae Salvationis (15th C)|
We are told towards the start of Beowulf that from Cain sprang all those bad things, including ogres and elves and giants and orcs and alcohol and flesh-eating bacteria, and then specifically that Grendel is himself of Caines cynne (Cain's kin). In case we still don't get it, line 1256 tells us that after Abel's murder, "then awoke many a fateful spirit, one of which was Grendel". Because of this association with Cain, Grendel often assumed giant status, relating to the Old Testament narrative of the Nephilim in Genesis.
|Calm down, it's a hoax|
Basically (this plotline is mostly from the Book of Enoch), God decided he needed some angels to watch over the antics of the people down on earth. These angels, sleazebags that they were, soon began to lust for the women below, and with a little encouragement from Samyaza (their leader), they go ahead and impregnate the women, and thus they become fallen angels (God creates quite a few of these doesn't he?).
The Nephilim are a result of this union between the Watchers (the sons of God) and mortal women (daughters of men, descendants of Cain), and apparently angels and mortal women make rather ugly babies, or at least, that's how the legend goes - at least in Enoch. If you have seen Noah, you may notice that the Watchers here are depicted as big stone giants - I don't know where I was going with that, but we shall leave it there.
|Paradise Lost - Gustave Doré|
In Genesis however, the most info we get about these Nephilim, besides their ancestry, is that they are "mighty men of old, men of renown" - Whut? Aren't they big fuck-off cannibalistic giants? In Enoch, yeah, but in Genesis, not necessarily.
And again, there has been a tiny bit of debate surrounding the word Nephilim itself - נְפִילִים - there it is in the Hebrew. In his Concordance of Hebrew words in the Bible, Strong lists Nephilim's etymology to naphal, which means "to fall", and he notes that Nephilim is "properly, a feller" or one who makes someone else fall. So...not necessarily a giant, as it is so often translated. And well, I know absolute eff-all about Hebrew, so I can't really make a greatly informed analysis here, but it may be possible that these Nephilim were not giants - rather, being "mighty men of old, men of renown", they were "gigantic" in another sense - in the sense of power.
Another thing about Cain, is that his descendants are supposed to bear his mark - is Grendel's "mark of Cain" his gigantism, if he is a giant? Or... is it even a physical mark? According to Augustine of Hippo, quite the influential figure for Anglo-Saxon Christianity, those marked by Cain were pretty much just...Jews. Yerp. Augustine also believed that if they renounced Judaism and went over to Christ, they would be grand.
So... this leaves the possibility that Grendel showed no physical mark (or at least not make him automatically monstrous) and that he could (if he so wanted) seek redemption.