Irony in Beowulf

Chapter VIII 1
"my dear Unferth..."   (Chapter VIII)

Because he is a guest, Beowulf must remain somewhat respectful towards Unferth. However, notice the patronizing tone he takes in the rest of this sentence by accusing Unferth of only speaking his mind when intoxicated. Beowulf then proceeds to tell the correct version of the story to the room.

"a gargantuan and ancient blade..."   (Chapter XXIV)

Since Grendel and his mother were impervious to human-made weapons, there is irony in the fact that Grendel's mother is killed by a weapon used by her own ancestors against humankind.