Menzan talked about “the frozen blockage of thought and emotion”; how it obstructs our practice and our life.
To understand what he meant, we need to distinguish between emotion and feeling. Feeling is our lived, momentary, felt response from moment to moment, fluid. Emotion is frozen feeling.
Something arises in the body. We then say “I am anxious”, then we speculate why we might be anxious, and the whole process of rumination starts. The thought and the emotion aren’t separate.
And we may imagine that this frozen mass obstructs our mind, but in fact it obstructs our heart. It is there like a blockage in the throat, preventing the heart emerging into the world.
If we do not understand this, our Zen will be too cognitive, it will lack feeling: Zen is not our liberation from feeling, but our liberation into it.