Elijah is about the emptiness that follows a death. The speaker says that since "he" died, there's a "pit" inside them, a hollow feeling they can't explain. They don't even know whether it's "friendly," which is a strange, almost childlike way to put it, as if the pit were an animal or a stranger they haven't figured out yet. The title suggests the person who died is Elijah, though the poem never says how he was connected to the speaker.
What stands out is how plainly the feelings come out. Everything seems "more scary," and the speaker simply repeats, "I'm scared." Then comes the last turn: they're sad, but believe Elijah wouldn't want them to be, so they pretend to be fine. The mood is quiet, raw, and a little lonely. The short lines and simple words make it feel like a private confession, a moment where the mask slips and the speaker admits what they hide from everyone else.