He is a 'herald appointed to Hades,' and this is on the strength of his ordination… a formal preparation and appointment. This 'making ready' is in Greek linguistic use an ordination, even if it be so only in a figurative sense.
Keréni argues that Hermes's installation as psychopomp constitutes a genuine ordination — a completed preparatory rite that confers his liminal office between the living and the dead.
, Hermes Guide of Souls, 1944thesis