A speaker sits alone at sunset and refuses to look back. There are no regrets here, only a steady focus on tomorrow, which comes back as the last line of every stanza like a quiet promise the speaker keeps repeating.
The middle of the poem brings a darker note. A breeze passes with a moan "filled with sorrow," and the speaker hears in it a soul being set free. The poem doesn't say whose soul it is, so it could suggest a death, or perhaps a burden being let go. Either way, the speaker stays put and keeps dreaming. In the final stanza the light fades completely, yet "something fills the hollow," a hint that an emptiness is being eased. The speaker smiles in the "ghostly mists."
The mood is calm and wistful, tinged with grief but ultimately hopeful. Sadness and comfort sit side by side, and the repeated refrain makes hope feel like a habit the speaker holds onto as the day goes dark.