不辭而去 He Departs Without Leave
噫！我卻還害酒哩。假若被他築上一鈀，卻不滅了這個威風，識破了那個關竅？且等我回家看看，是我的兒子不是我的兒子，再與他說話不遲。」好妖怪，他也不辭王駕，轉山林，徑去洞中查信息。噫！我却还害酒哩。假若被他筑上一钯，却不灭了这个威风，识破了那个关窍？且等我回家看看，是我的儿子不是我的儿子，再与他说话不迟。」好妖怪，他也不辞王驾，转山林，径去洞中查信息。
逐句解 Line by line
Ah!
噫, yī, again — the same exclamation that marked Sha Seng's joy now marks the demon's wavering. The storyteller uses it as a hinge.
But I am still muddled with drink.
害酒, hài jiǔ, literally "to be ill of wine" — to be hung over. It is the reason he does not fight, and therefore the reason he dies.
Should he land me a blow of his rake, would it not quench this majesty of mine and lay bare the whole contrivance?
The fear underneath the reasoning is about dignity, not survival. 築上一鈀, zhù shàng yì pá, to be struck a blow of the rake — Bajie's nine-toothed 鈀, read pá. 關竅, guān qiào, the crux, the secret joint of a thing: he is worried that a public thrashing would show the court what he really is.
Let me first go home and see whether they are my sons or not, and it will not be too late to speak with him after."
看看, kàn kan, to have a quick look; 不遲, bù chí, "there will be time enough after." The prudent option, chosen for prudent reasons, and it is the wrong one.
Bold fiend — without so much as taking leave of the king, he turned to the hills and woods and went straight to the cave to look into the news.
好妖怪, "bold fiend," is the same storyteller's cry of admiration used of Wukong on the crag — the narrator hands it out evenhandedly. 不辭王駕, bù cí wáng jià, without taking leave of the king; 查信息, chá xìn xī, to look into the news. That discourtesy will cost him more than the fight would have.
The demon's decision to verify rather than fight is his undoing, and the passage lays the reasoning bare: still fuddled with drink, and afraid that a blow of Bajie's rake in front of the court would strip away his majesty and expose his true nature, he takes the seemingly prudent course of slipping home to check on his children. Prudence hollowed out by vanity and a hangover leads him exactly where his enemy wants him.
His departure "without taking leave of the king" is a fine stroke of plotting, because it is this very abruptness — as the next passage shows — that confirms the court's suspicion of what he is. In escaping one snare he springs another, and hurries toward the cave where the disguised Great Sage is waiting with a widow's tears ready.