A speaker sits alone in the evening with letters written by someone who is no longer there. The poem never says who "her" is, or how she was lost, but the word "dead" suggests she has died, or at least that the letters have lost their living voice. We can only infer the relationship from the closeness of the details.
What stands out is how alive the letters still feel. Her "old talk" clings to "every object," as if the room itself has absorbed her way of speaking. The letters seem to call to the speaker's pen, nudging him to write back, even though no one can answer. The final words, "so close," hold two feelings at once: the comfort of her presence in the pages and the ache of knowing she is out of reach.
The mood is quiet, hushed and tender. Short lines and plain wording leave plenty of silence around them, much like the stillness of the evening itself. The title, "Devout," hints that this solitary ritual of reading and answering is something like prayer.