This poem uses imagery (creating a picture in words) relating to two discrete areas: the narrator's life indoors shown in the first line, and then the seemingly glorious and elevated events of the outside world.
The opening line also uses sibilance (repetition of the "s" sound) which gives the poem a whispering, hushed tone to the poem. This is also used later in the poem.
The repetition (repeating a word) of "unmoved" illustrates the firmness with which the female soul chooses her associations and sticks with them.
The metaphor (describing one thing as another) of "closing the valves of her attention" is an unusual one: taking us right into the heart where such allegiances (or rejections) of others' are made.
The final simile (comparing one thing to another using like or as) of "Like stone" shows the determination of the soul in establishing her relationships, and the stubbornness with which she retains her position.
Alliteration is stylistic device when the first consonant in a series of words is repeated. In the opening line of the poem, the speaker employs alliteration by writing "Soul selects...Society." The repetition of the consonant "s" makes this an example of alliteration.
Personification is when a non-human object is given human attributes. Throughout the poem, the speaker personifies the soul as a female by referring to it as a "her" and "she."
Enjambment is when a phrase or clause in one line of a poem moves to the next line without a terminating punctuation mark. In the second stanza of the poem, Dickinson employs enjambment by continuing the last word in the third line (kneeling) into the first word of the fourth line (Upon) without using a terminating punctuation mark.