The speaker tells us that she lives in a house with lots of doors and windows, which just so happens to be a way prettier house than "Prose." So we assume this house is a metaphor for poetry.
The speaker goes on to describe her poetry-house with lots of nature imagery. It's got trees for rooms, the sky for a roof—cool stuff like that. She ends by telling us how awesome the visitors to the house (readers of her poetry) are. Then she tells us that writing poems—or the life of the mind—is the best way she knows to reach for the divine.
And how.