Following the thread on 'Isis' a little while back, one or two ideas:
'Desire' is an album with a strong female presence - musically (Emmylou and Scarlet Rivera), and in the songs ('Sara', 'Oh Sister', 'One More Cup of Coffee', the mystery woman in 'Black Diamond Bay'). indeed there is a certain counterpoint between 'male' and 'female' themes, with the 'typically' male figures of Hurricane and Joey (boxer and gangster) being played off against Isis and Sara, who dominate their eponymous songs. This makes 'Desire' quite a different experience from, say, 'John Wesley Harding', where most of the songs evolve in a harshly all-male world (barring a temptress, a brothel and the two concluding love-songs).
But back to 'Isis': if 'Sara' is an elegy to a lost 'mystical wife', 'Isis' expresses the hope that the 'mystical child', the archetypal female, may, if lost, be found again.
The narrator seems to have difficulty in integrating and accepting his own female side, the creative force within symbolized by his goddess-named wife Isis, and that is probably why he loses her ('I could not hold on to her').
To get her back, he has to enter the strange, threatening dream-territory of the imagination. The landscape he traverses with the body-snatcher is a winter wasteland, unfertile, unresponsive ('the cold in the north', 'the devilish cold', 'the pyramids all embedded in ice', 'the wind it was a-howlin' and the snow was outrageous': as in 'Girl from the North Country' ('where the winters freeze and summer ends'), the wintry north country is the antithesis of love's warmth.
When the narrator accepts the body-snatcher's invitation, unbeknown to himself he is in fact taking the first step back to Isis ('when I took up his offer I must have been mad', BUT 'what drives (him) to (Isis) is what drives (him) insane'). On the journey, her symbolic presence is unescapeable: the tomb, the casket and the imaginary jewels are all emblems of the female body (Freud would interpret them as erotic dream-symbols) that he is unconsciously striving to understand and accept ('I was thinking about turquoise ... diamonds ... the world's biggest necklace').
Inside the tomb, he discovers that there are no real jewels ('no jewels, no nothing'), and no body either - but the true jewel that he seeks is Isis (as Sara too is a 'radiant jewel') , and the body he is really 'trying to find' is no corpse, but her living woman's flesh. The empty casket shows him that his search has been misguided, but must still continue. After his companion's death he realizes that it is Isis after all that he truly seeks, and he now pursues her not in the cold wasteland but in a warm, sensual landscape ('in the meadow where the creek used to rise').
And, after his brush with death and emptiness, at last when they meet he is able to accept both her and himself. The 'wild unknown country' of dream and the imagination has changed him ('you look different') beyond all recognition (that he's been 'no place special' is the wildest of understatements!), and Isis too is now willing to accept him.
The narrator has crossed the 'dividing line' between life and death, light and darkness, and returned to tell the tale - and at last there is no dividing line between male and female either, no beast howling on the borderline that separates man and woman:
'cruel death surrenders with his pale ghost retreating between the king and queen of swords'