Keats’s speaker makes a huge leap in the final stanza—a leap for which they have been preparing since they first perceived Psyche in the first stanza, reviewed her history in the second, and requested in the third that she allow him to be to her all the things she deserved but never had. In the final stanza, they not only worship Psyche but absorb her into their own mind and thus prepare themselves to open to the fullness of love, just as Psyche was able to receive Cupid.

In order to accomplish this, the speaker expands the capacity of their own mind; they find within it a previously unknown dimension in which they can accommodate Psyche. This is the “wide quietness” (Line 58) that exists in “some untrodden region” (Line 51) of their mind. From that deep inner place their thoughts fan out like branches of a tree; they are lofty, powerful thoughts, as suggested by the imagery of “wild-ridged mountains steep by steep” (Line 55).

Notably, the images of nature are grounded in a precise physiological detail that locates the speaker’s experience directly in their own consciousness. The “rosy sanctuary” (Line 59) they create for Psyche will be within the “wreath’d trellis of a working brain” (Line 60), an image that suggests a pattern of active neurons. The trellis is also worked on by the infinite variety of the speaker’s creative imagination, which produces a rich and celebratory tapestry of “buds, and bells, and stars without a name” (Line 61), endlessly “breeding flowers [that] will never breed the same” (Line 63). The excitement of the speaker seems to bubble over; they are thrilled at the knowledge that they are able to access the “loveliest vision” (Line 24) of all the gods and incorporate her most precious qualities. These images are no longer the “tuneless numbers” (Line 1) they apologize for in the first line of the ode, but a symphony of praise and exaltation.

To cap it all, the destination toward which the entire poem has been moving since the speaker first observed the divine lovers now comes into view. Within the “working brain” there will be “A bright torch, and a casement ope at night, / To let the warm Love in!” (Lines 66-67). Commentators have often noted that at the time of writing the ode, Keats had a love interest. This was Fanny Brawne, whom he had known since the previous fall. At the beginning of April, Fanny and her family had moved in next door to where Keats lived at Wentworth Place, Hampstead—this was just a few weeks before Keats completed the “Ode to Psyche.” As Keats’s biographer Robert Gittings puts it: “He was living with Fanny Brawne next door, at a wall’s thickness; French windows opened into the garden from her house just as they did from his” (John Keats: The Living Year, Heinneman, 1954, rpr. 1971, p. 128). Here is likely the origin of those last two lines. Keats’s speaker has done the work required of him to embody the divine Psyche and now they are ready to receive a divinelike love, too.