In the Epic poem of Beowulf, foreshadowing is of great importance throughout the poem. Before and after the heroic Geat goes into battle with Grendel's mother (lines 1491-1516) the significance of foreshadowing is shown through the use of alliteration and imagery as it shapes Beowulf's upcoming fate that eventually leads him to death. .
The first time foreshadowing is seen, is with the use of alliteration as well as imagery. It is, however, only the beginning of what's to come of Beowulf's fate. "Each by his head placed his polished shield/on the benches aloft/easily to be seen/were the ring-stitched mail-coat/steepling above the fray, and the stout spear-shaft" (1241-45). These lines use alliteration with the "s" sounds that describes only the beginning of Beowulf's preparation for his battle with Grendel's mother. It also give us the imagery of the armor before the battle. One can imagine and picture the armor all laid out waiting to be worn before heading into battle. "The armor of a hero/the manufacture of the mailed shirt/figured and vast/made it such a bulwark to his bone-framed chest/that the savage attack/could do no harm to the heart within" (1442-46). This description of armor is representative in its description of the idea of fate. The description, although always in the past tense, frequently looks ahead to what will happen either in the present, or in the future. This vivid imagery gives the reader its first sense of foreshadowing of Beowulf's potential triumphant victory of the epic battle between monster and warrior. .
The imagery between darkness and light gives the reader a glimpse into the foretell of Beowulf's upcoming battle with Grendel's Mother. "The Weather-Geat prince/dived into the Mere/the waves closed over the daring man/it was a day's space before he could glimpse the ground at the bottom." (1491-95) As Beowulf dives into the darkened depths of Grendel's mothers' lair, beneath a motionless lake of bloodstained water, it is seen that this scene represents the darkened imagery of the uncertain dangers lurking in this treacherous expedition.