The ‘true name’ is Ra’s soul and magic power (his libido). What Isis demands is the transference of libido to the mother. This request is fulfilled to the letter, for the aging god returns to the heavenly cow, the symbol of the mother.
Jung reads the Isis-Ra myth as a psychological allegory in which Ra’s ‘true name’ represents libido itself, and Isis’s demand enacts a forced regression of psychic energy back to the maternal principle.
, Symbols of Transformation, 1952thesis