How do the poetic devices contribute to the overall meaning of the poem, "Safe in their Alabster Chambers" by Emily Dickinson?

Well, the answer to this question depends a lot on which
version of the poem you are referring to. Dickinson wrote two, and they are both
markedly different. Stanza one is virtually the same in each version. The dead lie in
their graves, finally "safe" from the world, awaiting resurrection. This image of the
dead is juxtaposed in the first version of the stanza two with images of a joyful
natural world, and in the second version with images of a cold and indifferent
universe.

The first word of the poem, "Safe," might give a
certain smug confidence to the "elect" that the poem suggests may not be justified. The
unjustified smugness may also be implied by the manner in which the soft but heavy
alliterative "m" of "meek members" is offset by the harder alliterative "r" of "Rafter"
and "Roof." They may have their satin-lined coffins and their confidence in
resurrection, but their reality is suggested by the way they are cut off from all
vitality and sensation by the "Roof of Stone." The dead, in their "Alabaster Chambers,"
seem suspended in some cold white prison. They are untouched by "Morning," associated by
hope, or by "Noon," which we might associate with fulfilment and
intensity.

However, in the earlier version, stanza two
contrasts the coldness and suspension of the dead with the vibrancy and activity of
nature. The alliterative effects now change to support this sense of vibrancy as is
demonstrated in such phrases as "Light laughs the breeze" and "Babbles the Bee." Perhaps
Dickinson is using these natural images to offer consolation in the fact that in spite
of the death of the individual life goes on and the cycle
continues.