Thunder bursts from the earth and hearts are glad together. The text favors shared gladness that moves in step with others and warns against private indulgence.
Earth ☷, whose quality is yielding, lies below thunder ☳, whose quality is movement. Zhu Xi reads yu as harmony and gladness: people's hearts are at ease and respond to the one above, the single yang line in the fourth place, whose aims can therefore be carried out. Yielding and then moving, the time favors setting up a ruler and sending out troops.
Judgment (卦辭)
The text attached to the whole hexagram, read when no line is changing.
豫，利建侯行師。
Yu. It is favorable to establish lords and set troops in motion.
Yu means harmony and gladness: people's hearts are glad, and they respond to the one above them. The fourth line, the only yang, is answered by every yin line above and below it, so its aims can be carried out. Earth meets thunder, yielding and then moving. For these reasons, Zhu Xi says, the hexagram favors setting up a ruler and sending out troops. The gladness meant here is that of many people moving together, which the lines will set against pleasure taken only for oneself.
Image (大象)
The Image commentary (象傳) reads the whole hexagram from its two trigrams.
雷出地奮，豫。先王以作樂崇德，殷薦之上帝，以配祖考。
Thunder bursts out of the earth: Yu. The former kings, accordingly, made music to honor virtue, and offered it in grand style to the Lord on High, with their ancestors alongside.
Thunder breaking out of the ground, Zhu Xi says, is harmony at its height. When the former kings made music, they copied that sound and took its meaning as well. Yin, he notes, means grand. The image joins delight to music used for honoring virtue and for the rites to the Lord on High and the ancestors.
Lines (爻辭)
From the bottom line to the top. In the line names, nine (九) marks a yang line and six (六) a yin line.
Line 1, yin (初六)changing line in the shared reading
鳴豫，凶。
Proclaiming its delight. Misfortune.
A soft, petty line, the first has a strong backer in the fourth line and finds itself riding the moment and in charge. Zhu Xi says it cannot contain its pleasure and trumpets it, which is the way of misfortune. He also explains the hexagram's double sense: the judgment speaks of many people glad together, while every line except the fourth shows pleasure taken for oneself, which is why the lines differ in good and ill.
Line 2, yin (六二)changing line in the shared reading
介于石，不終日，貞吉。
Firm as stone. Not waiting for the end of the day. Correct and firm: good fortune.
Delight easily carries people away, Zhu Xi warns, and once carried away they end in sorrow. Only this line is both central and correct, so while the lines around it sink into pleasure, it holds itself steady, hard as stone. Calm and solid, its thinking is clear, and it sees the first signs of things before the day is out. He quotes the Daxue: calm, then able to think; thinking, then able to attain.
Line 3, yin (六三)changing line in the shared reading
盱豫悔，遲有悔。
Looking upward in delight. Repent; if slow, there is regret.
Xu means looking up. Yin in the wrong place, the third line sits just under the fourth, master of the hexagram, and gazes up at it while sinking into delight below, so it has reason for remorse. Zhu Xi reads the text as urging a quick change of heart: if the remorse comes late, there will surely be cause for regret. Timing turns the same feeling from a remedy into a burden.
Line 4, yang (九四)changing line in the shared reading
由豫，大有得。勿疑，朋盍簪。
The source of delight. Much is gained. Do not doubt: friends gather swiftly.
The fourth line is the very reason the hexagram is called Yu, the one yang line that all the others answer, so the text speaks of great gain. Zhu Xi adds a condition: it must be wholly sincere and free of doubt, and then companions will come together and follow it. Zan, he notes, means to gather and also means quickly.
Line 5, yin (六五)changing line in the shared reading
貞疾，恆不死。
A lingering illness. Yet for a long time it does not die.
Soft in the ruler's seat during a time of delight, the fifth line has sunk into pleasure, and it rides on the firm fourth line, to whom everyone else is drawn. Without support and in a precarious position, it is pictured as chronically ill; because it is central, it is also pictured as lasting without dying. Zhu Xi says the prognosis lies within the image itself. The illness pictures a weakened position, not a body.
Top line, yin (上六)changing line in the shared reading
冥豫成，有渝无咎。
Blinded by delight. The matter is done, yet it can change. No blame.
Soft at the very peak of delight, the top line is lost in pleasure, its sight dimmed. Yet it belongs to the moving trigram, so Zhu Xi sees a matter that, though already complete, can still change course; if it does, it can make up for its faults and incur no blame. The line, he says, opens wide the door to turning toward the good. Even this late, change remains possible.
If you drew this hexagram
Which text to read depends on how many lines are changing. With none, read the judgment; with one, read that line; with more, follow Zhu Xi's rules in the Yixue qimeng.
Text: Zhu Xi, Yuanben Zhouyi benyi (原本周易本義), Siku Quanshu Wenyuange copy, as transcribed by the Kanseki Repository (KR1a0031), corrected and punctuated by K-magpie. Translation and explanation: written by AI (Claude) from Zhu Xi's commentary and checked against the text and commentary. Sources and the list of corrections are on the Today's Hexagram page.