| Quote #1 He remembers hall-warriors and treasure-taking, |
Memory plays an important role in the awareness of transience. Only through a comparison with past – where hall-warriors feasted and received treasure – and the empty present does the speaker become aware of how much has disappeared, and with that, the joy that once existed.
| Quote #2 . . . I know not, throughout this world, |
The abandonment of the hall here is either a metaphor for death or a literal description of exile. Exile and death are similar in the way in which both end the presence of a person in a particular place – with death, in a human body on earth; with exile, in a community. Both death and exile remind the speaker of transience, how the earth "fails and falls."
| Quote #3 A wise man perceives how ghastly it will be |
The word translated here as "ghastly," gastlice, means both "ghost-like" and "awful" in Old English. It's a pun that expresses both the terribleness inherent in a deserted, abandoned earth, and the absence of the human souls whose memories now haunt it like ghosts.