Upright, the Hermit is about a time of solitude and introspection, of investigation, learning, enlightenment and sometime teaching. Reversed....
1) Opposite: If we take "opposite" to mean the negatives of the card then we can view the reversed card as all the evil stereotypes of hermits. The mean old man, isolated, misanthropic, paranoid. In this instance, isolation does not bring insights and epiphanies, but rather turns the person sour and against the world. We might well get reversed Hermit for men like the Unabomber, using their isolation to formulate crimes and destruction.
Other opposite of the Hermit is the Fool. Such as a teacher who uses his position to do foolish or childish things rather than to impart wisdom and insights. Either way, this is not a trustworthy teacher or sage.
2) Blocked: The power of the Hermit - his energy - is in his lantern. The Hermit has keen insight, and an ability to see what is hidden to others, to look beneath the surface. If this is blocked, then we might well say that the Hermit's lantern has been shuttered. It offers no light and the Hermit is left in darkness.
Thus, if reading this card as blocked, a reader might say to a querent that they are having trouble shedding light on a problem, or that they're alone in the dark in this situation. To get out, they must find a way to rekindle their lantern. The lantern is emblematic of their keen mind, sharp eye, and analytical abilities. Though currently in darkness, the hermit has the means to shed light on things if he'll just rekindle his lantern.
3) Upside-down: the most telling thing about the Hermit upside-down is that he loses his lantern. This is similar to the blocked interpretation, only worse. In the blocked interpretation the lantern can be re-illuminated. But upside-down, the lantern is gone. The Hermit is totally in the dark...and all alone. He has lost all ability to find his way and is going to have to stumble on home if he can.
I would see this extreme example in the case of people having some mental problems - they can't concentrate, they can't think, they can't remember or see things clearly anymore. An elder who is foolishly giving away his money, for example, might well be a Hermit reversed. A once wise and canny old fellow who seems to have completely lost his lantern, his ability to make intelligent decisions.
Curious about this card when upright? Go to our Tarot Card Meanings.