I need help developing a statement for the poem "Because I Could Not Stop For Death" by Emily Dickinson.

I assume you are referring to a thesis statement. One of
the aspects that critics praise this poem for is the way that Dickinson in this
excellent poem manages to tame or domesticate one of the most powerful and unavoidable
of human experiences through the use of a metaphor. In this poem, Death is compared to
an unexpected ride in a horse-drawn carriage that takes the speaker ever-onward into
"Eternity." This should provide ample scope for a thesis statement discussing the
presentation of death and how he is transformed from a scary figure into a kind, polite
and unhurried gentleman, "kindly" stopping, not knowing any
"haste."

Therefore a good thesis statement you might want
to use could be:

Through the use of metaphor Dickinson
domesticates death.

Consider how death is presented and how
the speaker responds to Death in this poem. Good luck!