沙僧被擒 The Rout
那獃子道：「沙僧，你且上前來與他鬥著，讓老豬出恭來。」他就顧不得沙僧，一溜往那蒿草薜蘿荊棘葛藤裡，不分好歹，一頓鑽進。那管刮破頭皮，搠傷嘴臉，一轂轆睡倒，再也不敢出來。但留半邊耳朵，聽著梆聲。那怪見八戒走了，就奔沙僧。沙僧措手不及，被怪一把抓住，捉進洞去。小妖將沙僧四馬攢蹄綑住。畢竟不知端的性命如何，且聽下回分解。那呆子道：「沙僧，你且上前来与他斗着，让老猪出恭来。」他就顾不得沙僧，一溜往那蒿草薜萝荆棘葛藤里，不分好歹，一顿钻进。那管刮破头皮，搠伤嘴脸，一毂辘睡倒，再也不敢出来。但留半边耳朵，听着梆声。那怪见八戒走了，就奔沙僧。沙僧措手不及，被怪一把抓住，捉进洞去。小妖将沙僧四马攒蹄捆住。毕竟不知端的性命如何，且听下回分解。
逐句解 Line by line
Said the blockhead, 'Sha Monk, you go up and keep fighting him a while — let Old Zhu go and relieve himself.'
The excuse is worth savouring. 出恭 is the genteel way to say you need the privy, and it comes from the examination halls, where a pair of plaques stood at the entrance reading 出恭 and 入敬 — go out respectfully, come back reverently — and a candidate who needed to leave the room took one up on his way. So the most decorous phrase in the language for needing the toilet is being deployed, mid-battle, as cover for desertion. 與他鬥著 takes 著 as the ongoing zhe: you keep fighting him.
And with that, giving no further thought to Sha Monk, he bolted in a streak into a tangle of wormwood and creeper, bramble and vine, and, heedless of everything, went burrowing in at a rush.
顧不得沙僧 (得 = dé) is "could not attend to Sha Monk," which is a generous way of putting it. 一溜 is in a streak, at a dash. The undergrowth gets four plants and no shortcuts — 蒿草薜蘿荊棘葛藤, wormwood, wall-creeper, bramble and kudzu vine — because the novel wants you to feel how thoroughly he buries himself. 不分好歹 (分 = fēn) is heedless of good or ill; 一頓鑽進 is to burrow straight in.
Little he cared that it scraped his scalp raw and jabbed his snout and face; he rolled himself over and lay down, and would not come out again — but kept half an ear cocked, listening for the clapper's sound.
The detail that makes the whole thing: he leaves half an ear out. 梆聲 is the sound of the watchman's wooden clapper, the signal he is waiting for before it is safe to reappear. 那管 takes 那 as nǎ, "what does he care for"; 搠傷 (搠 = shuò, to jab) 嘴臉 is thorns jabbing his snout and face; 一轂轆 (轂轆 = gǔ lù, a rolling motion) 睡倒 (倒 = dǎo) is to roll over and lie down. Comic cowardice does not get more exactly observed than this.
The demon, seeing that Eight Rules had gone, rushed straight at Sha Monk. Sha Monk, caught off his guard, was seized in the demon's grip and hauled into the cave; and the little imps bound him fast, all four limbs trussed together.
措手不及 — caught with your hands not ready — is still the ordinary Chinese for being taken completely off guard, and it is the last thing said of Sha Monk before he vanishes into the cave. 一把抓住 is seized in one grab; 將 (jiāng) takes him inside; 四馬攢蹄 (攢蹄 = cuán tí, hooves drawn together) is the hog-tie, all four limbs bound behind. The phrase is drawn from trussing livestock, and it is being used on a monk.
In the end, there is no knowing how it truly went with his life — so listen to the next chapter for the telling.
畢竟 is "in the end," 端的 is "truly, for certain," and 且聽下回分解 (分 = fēn) is the invariable sign-off of a chapter — "pray hear it explained in the next instalment." It is the cliffhanger as a piece of trade equipment: the storyteller wants you back tomorrow, and he has left a man tied up to make sure of it.
Eight Rules' desertion is the chapter's most vivid piece of comic cowardice. As the fight turns against him he pleads a call of nature — let Old Zhu go and relieve himself — and on that flimsy pretext abandons his brother outright, bolting headlong into wormwood and bramble. The novel dwells on the physical comedy of the flight: heedless of the thorns scraping his scalp and jabbing his snout, he rolls over, lies low, and refuses to come out — while keeping half an ear cocked for the watchman's clapper, ready to reappear the moment it is safe. The portrait is unsparing and affectionate at once, and it is Eight Rules exactly: appetite and self-preservation beating loyalty, wrapped in the thinnest available excuse.
With one disciple in the weeds and the other quickly overpowered and trussed, the rescue mounted with so much confidence collapses entirely, and the chapter closes on Sha Monk hauled into the cave. The reversal is complete. The courtly comedy of Baoxiang, the boasts, the imperial wine, the golden tablet — all of it has ended in rout, and both of Tripitaka's fearsome disciples are now out of action, one hiding and one bound. The storyteller's closing formula leaves the outcome hanging, but the shape of the need is already plain: this demon will not be beaten by the companions who remain, and the next chapter will have to reckon with the one they sent away.