Hexagram 21, Fire over Thunder: Biting Through (Shi He), is the 21st of the 64 hexagrams of the I Ching. It is made of Li (fire) above and Zhen (thunder) below, a picture of thunder and lightning together, and it speaks about biting through whatever blocks the way so that things can come together.

Hexagram 21 (Shi He) at a Glance

Attribute	Detail
Number	21 of 64
Name	Fire over Thunder: Biting Through (Shi He)
Image	☲ over ☳ (fire over thunder, thunder and lightning together)
Inner (lower) trigram	Zhen ☳, thunder
Outer (upper) trigram	Li ☲, fire and light
Element	Upper trigram Li is Fire, lower trigram Zhen is Wood
Overall tone	Success, through decisive handling of what is in the way
Key phrase	Success; favorable to use legal action
Yang lines	3 of 6
Opposite hexagram (every line flipped)	Hexagram 48, Water over Wind: The Well (Jing)
Inverted hexagram (turned upside down)	Hexagram 22, Mountain over Fire: Adornment (Bi)

The Original Text and Its Meaning

This part gives the classical wording of Hexagram 21 in English, with a plain explanation. If you only care about how the hexagram applies to daily life, feel free to skim it and jump to the later sections.

The Judgment

Biting Through: success. It is favorable to use legal action.

In plain words: "biting" is to bite, and "through" is to close up. Biting Through means biting through the object caught between the jaws so that the mouth can close. "Success" is smooth passage, and "favorable to use legal action" means it helps to handle judgments, cases and discipline. The whole hexagram paints a clear scene: something stands between two sides, and it has to be bitten through before the two can meet. It is one of the few hexagrams that speak openly about law and about firmness toward whatever is blocking the flow of work.

The Image

Thunder and lightning: Biting Through. In the same way, the ancient kings made penalties clear and set their laws firm.

In plain words: thunder and lightning together make Biting Through, and the kings of old, following this image, made punishments clear and laid down the law. Thunder is the force of authority, and lightning is the light that shows a matter plainly. Put together, they give the principle of whoever holds the rules: be strict, but be clear first. Nothing does more harm than a vague penalty. Someone who handles things well in a Biting Through time has both the light to see the problem and the authority to act on it.

The Six Lines

The six lines of Shi He describe six levels and situations of biting through an obstacle, from small matters to tense ones. Read from the bottom up: the first line is at the bottom, the top line is at the top.

Line	Classical text	Plain meaning
Line 1 (nine at the beginning)	Feet fitted in the stocks, the toes hidden; no blame.	A light restraint on a first offense, and no fault
Line 2 (six in the second place)	Biting soft flesh, the nose hidden; no blame.	Biting easy, tender meat so eagerly that even the nose is buried, and no fault
Line 3 (six in the third place)	Biting dried meat, meeting poison; slight regret, no blame.	Biting old cured meat and hitting a bad spot brings a small regret, but no fault
Line 4 (nine in the fourth place)	Biting dried meat on the bone, gaining a metal arrow; favorable in hardship and steadfastness; good fortune.	A tough bite that pays off with a metal arrowhead, and holding firm through the difficulty brings good fortune
Line 5 (six in the fifth place)	Biting dried lean meat, gaining yellow gold; steadfast and watchful; no blame.	A clean bite that wins gold, and staying steady and alert keeps it blameless
Line 6 (nine at the top)	Wearing the cangue, the ears hidden; misfortune.	A heavy wooden collar that covers the ears, and a bad outcome

Reading the Six Lines in Everyday Terms

The six lines of Hexagram 21 are a map of six ways to deal with a problem in the way, from a small slip at the start to a big fault built up over time. Here is each line in everyday language.

Line 1: Feet in the stocks, toes hidden. This is the picture of a light penalty for a new mistake. It is a first offense, not yet repeated, and a warning comes right away. A small sting is enough to remember it. The text is a single short phrase: no blame. In daily life, it could be a newcomer making a small error, a child telling a first lie, or a new hire missing a deadline. Dealing with it firmly at this point means it does not turn into a habit. If it is let slide, the fault tends to grow, and by Line 6 it is too late.

Line 2: Biting soft flesh. Tender meat is easy to bite, but the biter is so eager that the whole nose goes in. The hint is that even an easy case can go wrong when there is no restraint. In daily life, you may have the right to handle a subordinate's clear mistake, yet irritation takes over and you overdo it: harsh words, a penalty bigger than needed, shaming them in front of everyone. The matter was right, but the way went a bit too far. The text still says no blame, so the outcome is acceptable, but it is a lesson in self-control for anyone holding authority.

Line 3: Dried meat and poison. Line 3 is the hardest of the lower half. It is like biting into cured meat that has sat too long and hitting a spoiled spot. In daily life, you take on a problem that has piled up for ages, and once you start you find ugly things inside: wrong accounts, more people involved than expected, conflicts that run deep. The text says a small regret and no blame, which means the discomfort is real, but carrying through to the end is still not something to be blamed for. Do not drop it halfway just because it tastes bitter.

Line 4: Bone and meat, and a metal arrow. This is a fine line, and it comes with a reward. Dried meat on the bone is very hard to bite, but when it is bitten through, a metal arrowhead is found inside. It says that a hard task handled correctly may give you something worth more than the task itself. In daily life, you sort out a thorny case at work, expecting it to cost only effort, and afterward you gain credibility, the trust of your teammates or a new area of responsibility. The line adds that the benefit lies in staying steady through hardship. It is neither easy nor quick, and whoever lasts to the end may get the gold.

Line 5: Dried meat and yellow gold. The fifth line belongs to the person in the highest position when a matter has to be settled. The position is good and the task is not too hard, so biting the dried meat yields gold. But the text includes one important word, "watchful," meaning stay alert. Gains from holding the rules can easily make a person overconfident and sloppy, and then they decide wrongly. In daily life, picture a leader who has handled a few cases well and starts to think they are always right. The hexagram says: keep your alertness, and do not let a win turn into arrogance. That is what keeps you blameless.

Line 6: The cangue and the hidden ears. The last line is the heaviest warning of the hexagram. A big wooden collar sits on the neck, so large that it covers the ears. It is the picture of a fault that has piled up for a long time with nobody dealing with it, until the penalty comes down hard, and by then the person can no longer hear advice. In daily life, it is someone who has gone wrong again and again without anyone warning them firmly enough, until the consequences arrive and cannot be undone. The warning is not meant to frighten. It reminds us that fixing something early is nearly always cheaper than fixing it late. Line 1 and Line 6 are two ends of the same lesson.

If you want to cast a hexagram and see its reading, you can try it on HOROS.

What Hexagram 21 May Say About Everyday Life

Love

Casting Shi He on a love question often points to a relationship with something in the way that needs to be dealt with. It could be a long-running misunderstanding, a promise not kept, a third person who has influence, or a bad habit that one side will not drop. Someone single may still be tied up in an old connection that has not ended. The hexagram suggests speaking plainly and handling that sticking point decisively, rather than dodging it any longer. Line 6 is the warning: left alone, it hardens into a collar. A moment of honest, painful talk may be better than dragging out a comfortable pretense. Once the obstacle is bitten through, the mouth can close.

Career

On career, Shi He tends to land on someone handling a difficult situation at work: an employee who broke a rule, a partner late on a contract, a project that has stalled too long, or an internal dispute. It is a time that calls for decisiveness. Line 1 says that handling small faults early keeps them light. Line 2 says to handle things, but not to overdo it or humiliate anyone. Lines 3 and 4 say that once you start on a hard task you should see it through, even if ugly things turn up. For leaders, the Image is a compass: penalties should be clear and rules should be plain. People who deal with matters fairly and firmly tend to be trusted by their teams.

Money

On money, Shi He leans toward amounts tied to "handling" a matter: collecting a debt on time, recovering money owed, a contract dispute, dividing assets, or sorting out investments left hanging. It is not a time to give way too much. Lines 4 and 5 both carry a reward of "gold" or a "metal arrow" for those who handle things rightly. On the other side, the hexagram warns anyone who avoids a debt, has a tax error or is caught in murky arrangements: dealing with it early is nearly always cheaper than dealing with it late. The money of Shi He is money recovered through firmness.

Health

On health, Shi He speaks of blockage and setting things in order. If a small matter has been ignored for a while, or a habit you keep putting off, this is a time to face it: put the check-ups you need on the calendar and straighten out your daily routine one item at a time. Line 6 is a reminder that the longer you wait, the harder it gets to deal with. It is usually better to make up your mind and sort it out properly once than to live with a nagging worry for a long time. Leave anything that needs a professional judgment to medical professionals. Health in the spirit of this hexagram is the health of someone who dares to face a problem.

Closing Thought: Bite Early, Bite Firmly, Let Go Afterward

What stands out most in this hexagram is that it does not condemn decisiveness. It treats decisiveness as a way. The I Ching has Modesty to teach yielding and Following to teach going along, and it also has Biting Through to teach biting. Life does not always allow you to give way. Some wrongs, some messes and some blockages have to be dealt with. Deal with them early, while they are small. Deal with them firmly, but with measure. And once they are dealt with, do not carry a grudge. Those three beats are the way of Biting Through.