The High Priestess: what you know without being able to explain it
major arcana

What arcanum two adds to a spread, why it usually signals withheld information and how to read it reversed without turning it into a mystery.
The figure sits between two pillars, one light and one dark, with a veil behind her and a book or scroll half hidden. Almost everything in the card is half shown, and that is exactly its function within a spread.
Upright, it usually signals knowledge that exists but hasn't yet been put into words. The sense that something doesn't add up without being able to justify it, the piece of information someone isn't telling, the decision already made inside and not acknowledged out loud. It is a card of pause and listening, not of action.
In the obstacle position it works very concretely: what holds things back is that information is missing, or that what exists isn't being said. That makes the reading actionable, because the next question becomes who has that information and how to ask for it. Next to Swords, it's usually an avoided conversation. Next to Cups, something you aren't admitting to yourself.
It's best not to wrap it in vagueness. Saying the Priestess speaks of intuition and leaving it there helps nobody. A useful reading has to get specific: what is it that you know and haven't written down? That question, put that bluntly, usually produces an answer within seconds.
Reversed, there are two frequent readings. One, the secret coming to light or the information finally shared. The other, disconnection from that inner voice: decisions made purely on arguments, ignoring the persistent discomfort that was warning of something. The second often appears alongside Swords, which push towards pure reasoning.
If you pull cards regularly and the Priestess keeps returning on the same subject, the journal will show it. That repetition doesn't mean there is a mystery, it means you have gone a long time without writing down what you already know about that matter.