渾身是汗 Sweating Through His Hide
那老魔聞此言，渾身是汗，諕得戰呵呵的道：「兄弟，我說莫惹唐僧。他徒弟神通廣大，預先作了準備，磨棍打我們，卻怎生是好？」教：「小的們，把洞外大小俱叫進來，關了門，讓他過去罷。」那老魔闻此言，浑身是汗，諕得战呵呵的道：「兄弟，我说莫惹唐僧。他徒弟神通广大，预先作了准备，磨棍打我们，却怎生是好？」教：「小的们，把洞外大小俱叫进来，关了门，让他过去罢。」
逐句解 Line by line
At these words the old fiend broke out in a sweat all over, and said, shaking and stammering with fright, "Brothers, I told you not to provoke the Tang monk.
諕 is xià, to frighten — the character looks like it should be háo and the sealed chapters correct it to xià every time. 諕得 then takes the light de, the grammar that hangs a result off a verb, so the shape is frightened-so-badly-that. Three earlier chapters spell it exactly this way.
His disciple has vast magic powers. He has made his preparations in advance, and he is grinding a cudgel to beat us with. What are we to do?"
Note how fast the lie has hardened. Wukong reported a giant who might be Sun Wukong; the chief has already converted that into a settled fact with a motive attached — 預先作了準備, he has made his preparations in advance.
He ordered: "Little ones, call in everybody outside, great and small, shut the doors, and just let him go past."
罷 is bà here, the word of weary resignation that ends a suggestion — let him go past and have done. The sealed chapters run thirty-eight bà against four of the lighter ba, and all four of those are one pleading formula in a single chapter.
One speech, and the demon army is being recalled from the field. This is the payoff of the whole disguise, and it costs Wukong nothing but talk.
What sells it is that the chief is not stupid. His reasoning is sound at every step: the disciple is powerful, the giant was preparing, therefore shut the doors and let the threat pass. He has simply been given one false premise at the start, and everything downstream of it is impeccable. That is how good lies work in this book, and Wukong is about to find out that it is also how they fail.