The speaker stands facing a powerful light, and because of that, no shadow falls in front of them. But the light isn't comforting. It burns, and the speaker feels it wants to turn their whole existence to ashes. Light here seems less like hope and more like a force that consumes.
Then the poem turns. The shadow is now behind the speaker, and they want to leave it and step into the light. Yet the shadow is tied to their feet and follows wherever they go. It can't be shaken off. The speaker and the shadow seem bound together, almost like two halves of one self.
The ending is bleak and quiet: once the speaker enters the light, neither self nor shadow remains. The mood is tense and restless, moving from struggle to a kind of dissolving. The poem suggests that to reach the source of light fully, one may have to give up identity itself.