The card represents both the quest (the searching light) and the goal (the passage through the cave into the light of the world); it's also both the path and the destination/attainment.
It took me a long time to figure out what Barrett meant by this line in the companion book, "The Absolute is the source of all things and is the goal of existence." This is what I finally came up with - If the Absolute is the source of all things and the goal of existence is reconnecting with the Absolute, then the Hermit expresses the search for the Absolute.
The Hermit's lantern is the bright light of wisdom in the all-pervading darkness (the cave) of ignorance. It's also reason that stands its ground against fear. The darkness of the cave represents the subconscious, irrational fears and ignorance. The light represents wisdom, knowledge and logic.
The Virgo attribution of the card, the association with the letter Yod and the ear of wheat that the Hermit holds all suggest fertility. The wand he holds is another symbol of procreative power. These symbols of fertility and procreation suggest the world of possibility that is available to those who are able to follow the Hermit's path and reconnect with the Absolute. The Hermit shows what may be achieved.
The ear of wheat may be associated with the staff of life. It also may suggest the need to harvest what one has sown. The wands suggests the untapped and limitless potential of the Hermit's search. The single point of light shows a singleness of purpose.
Yod means hand and can represent either the helping hand that reaches out in the dark or the blindly groping hand of one who is lost. Is the Hermit purposefully traversing the cave? Or is he lost? Is he providing the role of guidepost for those who are lost? Or does he stand there to show the souls of the dead the entrance to the Underworld?
The pomegranate is thought to be the food of the dead. Its presence at the edge of the chasm suggests that the chasm is the entrance to the Underworld, where the dead reside. The chasm has dual roles - it's both the abyss through which gods of the dead guided souls to the Underworld and the passage through which dead souls are lead out of the Underworld and back to life (coming out of the darkness and into the light of the Hermit's candle).
ETA - The bracelet that the Hermit wears is almost identical to the ones that Osiris is seen wearing in the Hierophant. But it's also similar to the one that Isis wears in the High Priestess. So either god could be the cloaked Hermit, as has already been pointed out in other posts.
Rodney