There is proverbial peace in sleep. Yet Jackson’s poem exposes the reality that a person is helpless when they sleep, without all the safeguards in place during the day to control dark thoughts, unpleasant memories, and the emotional residue of traumas that are sometimes years in the past. To use the metaphor that Jackson offers, sleep frees our darkest and deepest “secrets” (Line 4) from the “houses” (Line 3) where we have chained them up in the sturdiest and stoutest chains we can “forge” (Line 5). That terrifying liberation is what sleep means to the speaker. Moreover, the poem notes, there is nothing a person can do except hope that eternal rest is not disturbed by such dreams.

“Oh, cruelty!” (Line 8), the speaker laments of their recurring bad dreams. Sleep does not provide a happy respite, nor can the sleeper assume that they will awaken refreshed, reanimated, and ready for a new day. Instead, for them, sleep is about negotiating with the past. Thus, each night, the speaker heads off to sleep understanding the reality of this vulnerability and anticipating the aching pain that sleep will inevitably trigger by immersing them in what they so desperately want to keep hidden, the very pain that the person manages to control during the day.