"azure-lidded sleep" is the first verse in stanza XXX from "The Eve of Saint Agnes". Is the reference you intended? If so, I have always interpreted it as Madeleine, with her blue eyes (hence the reference to "azure")is still asleep as Porphyro sneaks from her wardrobe where he's been hiding to set up that sumptuous feast before he awakens her and has his "way with her."
I am open to any other logical interpretations!!