Consulting the Book of Changes…
Hexagram 21 of 64 · King Wen sequence
Biting Through has success. It is favorable to let justice be administered. Thunder and lightning: the image of Biting Through.
The flame that clings to its fuel — perception, brightness, the eye that gives form to things.
Shock and movement from below — the impulse that breaks open winter and starts a new cycle.
Fire above, thunder below. Thunder and lightning: the image of Biting Through. Thus the kings of former times made firm the laws through clearly defined penalties.
Hexagram 21 — Biting Through — names a moment in which thunder sits beneath fire. What the I-Ching gives you here is not a prediction but a posture. It says: stand inside this configuration of forces, do not flinch from it, and act in the spirit of the image. The classical Judgment tells you what is at stake; the Image tells you what to do about it.
Apply it as a frame for the next concrete decision in front of you. If the question you brought is about action, ask whether the gesture you are considering matches the spirit of biting through. If it is about a relationship, look at the trigrams — Thunder beneath Fire — and ask which of those two energies you have been overplaying, and which you have been ignoring. The oracle is rarely cryptic on close reading; it is precise about what kind of person this moment is asking you to be.
Treat any changing lines as the seam where the situation is opening into its next phase. The transformed hexagram is not what will happen — it is what this one is in the process of becoming, and the changing lines are the hinges. Read them last. Read them slowly.
If a single line changes from yin to yang or yang to yin, the hexagram becomes one of these six.