Now the Deer-Power Immortal, seated on an embroidered stool and watching a good while, saw that the two upon the high terraces were neither winning nor losing; so this Daoist lent his elder brother a hand: from the short hairs at the back of his head he plucked one, rolled it into a pellet, and flicked it up, straight to the top of the Tang Monk's head, where it turned into a great bedbug and bit the elder fast.

The contest turns crooked, and it takes one sentence. Deer-Power is watching from an 繡墩, an embroidered stool; the two on the towers are 不分勝負, with nothing to choose between them (分 = fēn, "to divide"); so he cheats. A short hair from the back of his head, rolled into a pellet and flicked up, becomes a bedbug on the master's scalp. Both 將 here are jiāng, the small word that hands the verb its object or its direction — once for taking up the hair, once for flicking it away. 捻著一團 keeps 著 = zhe, holding the rolling open. 咬住長老: 長 = zhǎng.

The elder first felt an itch, and afterwards felt pain.

Both 覺 are jué, "to feel, to sense" — not the jiào that means sleep. Itch first, then pain: the order matters, because it is the itch that makes him move.

Now one who sits in meditation may not stir his hands; to stir the hands counts as forfeit.

The narrator stops the story to state the rule, which is how you know it is about to be broken: 坐禪的不許動手，動手算輸 — a sitter may not move his hands, and moving them forfeits the match. Everything that follows depends on this one line.

For a moment the aching grew past enduring, and he drew in his head and rubbed the itch against the front of his robe.

一時間: 間 = jiān, "for a spell." 疼痛難禁 — 禁 is jīn, "to bear, to withstand," not the jìn of forbidding. Both 著 in 縮著頭 and 就著衣襟 are zhe, holding the action open. Forbidden to use his hands, he scrubs the itch on his own collar: a man in real trouble, dressed as farce.

Eight Rules said: "That's bad — the Master's fallen into a fit of the falling-sickness."

羊兒風, "goat-wind," is a folk name for epilepsy — the sufferer's twitching limbs likened to a goat's. Its 兒 reads er, the small unstressed ending buried inside a fixed old compound. 發了 is "has come on," the standard verb for a condition flaring up.

Sha the Monk said: "No — it's a head-wind that's come on."

Sha Monk's rival diagnosis. 頭風 is literally a wind in the head — a splitting headache, and in Chinese medicine a real category rather than a figure of speech. 發了 again: "has started up."

The Pilgrim, hearing them, said: "My master is a man of true sincerity, a gentleman; if he says he can sit in meditation, then most certainly he can sit;

Wukong's defence of his master is oddly moving, and entirely wrong-headed. 志誠君子 is a man of true sincerity; and here is a reading worth catching, because this chapter uses 子 nearly forty times as a light unstressed ending and only twice like this — in 君子 it is the full zǐ, "master, gentleman," the Confucian word. 斷然會坐: assuredly he can sit.

if he said he could not, then simply he could not.

說不會，只是不會 — if he had said he could not, then he simply could not. The logic is perfect and completely beside the point.

A gentleman — how could there be any falsehood in him?"

君子家 — again the full 子 = zǐ, the gentleman. 豈有謬乎 is "how should there be error in him?" The question expects the answer no; the answer, unfortunately, is that there is a bedbug.

You two hold your peace; wait while I go up and take a look."

休言 is "say no more"; 等我上去看看, let me go up and take a look. Doubling 看 (kàn) makes it casual — just a quick look.