The poem is short and strange, and it works more by suggestion than by explanation. In the first stanza the speaker recalls an evening that feels "dangerous in memory," then states flatly, "I died." There is no drama in the delivery. The line arrives plainly, which makes it more unsettling. It could mean a literal near-death, but it might just as easily describe a moment when some old version of the self ended.
The second stanza shifts toward the body. The speaker's hands "understand" them, as though the hands know something the mind cannot say. Then the sentence slips into "or some melancholy any thing," where the grammar loosens and the meaning goes vague. That drifting feels deliberate, like a thought fading out. The title, "Decomposure," hints at both decay and lost composure, and the poem seems to come apart in just that way. The mood is hushed, sad, and a little eerie, with grief that stays unexplained.