It's coming the postponeless Creature — Passover

This poem is about Passover, hinted in the last line, "carries one out of it to God." Dickinson described this act, to smite all the firstborn, as Bold and Brief.

It's coming－the postponeless Creature－¹
It gains the Block－and now－it gains the Door－
Chooses its latch, from all the other fastenings－
Enters－with a "You know Me－Sir"?

Simple Salute－and certain Recognition－⁵
Bold－were it Enemy－Brief－were it friend－
Dresses each House in Crape, and Icicle－
And carries one－out of it－to God－

(F.556/J.390)

[1] postponeless:: that may not be averted, God's will.
[2, 3] Door, Chooses:: selects the door without blood; "when I see the blood, I will pass over you." (Exodus 12:13)
[4] Enters, know Me?:: enters houses of those who didn't recognize God.
[5] certain Recognition:: confirmation of the firstborn.
[6] Enemy, friend:: neither enemy nor friend.
[7] House in Crape, Icicle:: death signs of a house.
[8] carries one out:: takes away every firstborn.

For I will pass through the land of Egypt this night, and will smite all the firstborn in the land of Egypt, both man and beast; and against all the gods of Egypt I will execute judgment: I am the LORD. (Exodus 12:12)