The lad came out of the gate and called aloud: 'Who is it making a disturbance here?'

The cave's first words to the seeker are a complaint about the noise. 搔擾 (sāo rǎo) is to pester or disturb — the lad has come out to find whoever is rattling about in the pine tree.

The Monkey King dropped down out of the tree with a plop, came forward, bowed, and said: 'Immortal lad, I am a disciple come to seek the Way and study immortality —

撲的跳下樹來 — he drops out of the tree with a plop (撲 pū, with 的 standing in for 地 here, turning "plop" into a description of how he jumps), then bows (躬身, 躬 gōng). Watch the sequence. He was up a tree eating pine seeds a moment ago, and now he announces himself as 訪道學仙之弟子, a disciple come to seek the Way and study immortality (弟子 with 子 in full tone zǐ). He has had ten years to rehearse that line.

I would never dare make a disturbance here.' The lad laughed: 'You're a seeker of the Way?'

更不敢, "I would never dare" (不 in its bù form before the third tone of 敢). And the lad laughs — 你是個訪道的麼, "you're a seeker of the Way?" (麼, the little closing word that turns a statement into a question, read me). Somewhere between the pine seeds and the formal self-introduction, the joke has landed.

The Monkey King said: 'I am.' The lad said: 'My master has just risen from his couch to mount the dais and expound the Way.

正才下榻 — the master had only just risen from his couch (才 cái, "just," the 維基文庫 reading; 榻 tà, a low couch) to mount the dais and expound the Way (壇 tán, a raised platform). A teaching was about to begin.

Before he had even said why, he had me come out and open the gate,

The master broke off a lecture, gave no reason, and sent the boy to the door — nobody had announced anything. 還未說出原由 is the tell: he had not yet even said why. And 教 here is jiào, to bid or cause — the same character that was jiāo, to teach, in the woodcutter's mouth.

saying: “There's a seeker of cultivation outside — go and receive him.”

The master's own words, quoted: 外面有個修行的來了，可去接待接待, "there's a cultivator outside — go and receive him" (接待, to receive a guest, doubled in the easy colloquial way; 行 here xíng). This is the first thing we learn about Subodhi's powers, and it arrives as an offhand instruction to a servant.

It must be you?' The Monkey King laughed: 'It's me, it's me!'

想必就是你了, "it must be you, then." And the monkey's 是我，是我 — "it's me, it's me!" — is pure delighted character. Ten years of ocean and nine of nothing, and somebody inside was expecting him.

The lad said: 'Come in with me.'

跟 (gēn) is to follow. Four words, and the door he did not dare knock on stands open.

The Monkey King straightened his clothes, composed himself, and followed the lad straight into the depths of the grotto-heaven to look about:

整衣端肅 — he straightens his clothes and composes his face (端肅, grave and reverent). The creature who bowed to nobody is smoothing his coat down in the doorway. 洞天 is a Daoist "grotto-heaven," one of the sacred cave-worlds mapped across China's mountains, and 徑 (jìng) means he goes straight in.

tier upon tier of deep halls and jade towers, court after court of pearl palaces and shell gate-towers, quiet chambers and secluded dwellings beyond all telling.

一層層 is tier upon tier and 一進進 is courtyard after courtyard — a 進 being one section of a Chinese house, so this is a mansion running back through repeated courts, not a hole in a hill (闕 què, a gate-tower). 說不盡, more than can be told, takes 不 in its bú tone before the falling tone of 盡. The hermit's cave turns out to have a palace inside it.

On he went to the foot of the jade dais, where he saw Patriarch Subodhi seated upright upon it,

瑤臺 is a terrace of jade, the standard seat of an immortal, and 端坐 is to sit bolt upright. After a whole chapter of approach — song, woodcutter, tablet, lad, palace — the master is simply there, in plain view, sitting still.

with thirty minor immortals standing in attendance below. And indeed he was:

Thirty junior immortals standing in attendance (侍立, to stand in waiting). The woodcutter said thirty or forty; he was right about that too. 果然是 cues the verse portrait of the patriarch.

A Great Awakened Golden Immortal of stainless form, the wondrous-marked Patriarch Bodhi of the West.

And here is the surprise: the portrait of this Daoist master is a portrait of a Buddha. 大覺金仙, "Great Awakened Golden Immortal," was a Song-dynasty epithet for the Buddha dressed in Daoist vocabulary (覺 is jué, awakened, not jiào, sleep). 沒垢姿 is a form without defilement (垢 gòu), and 西方妙相 invokes the lakṣaṇa, the bodily marks of a Buddha (相 xiàng). Everything points west — to India, to the Buddha — about a man who is going to teach Daoist alchemy.

Unborn and undying, through the three-times-three practices; whole in breath and spirit, boundless in compassion.

不生不滅, unborn and undying, is straight Buddhist doctrine (anutpāda-anirodha); note the tones, bù before the level 生 but bú before the falling 滅. 三三行 is genuinely obscure — some "three-times-three" set of practices (行 here xíng) — and pairs with 萬萬慈, boundless compassion (慈 cí). Meanwhile 全氣全神 is inner-alchemy shorthand for keeping breath and spirit whole. Two systems, one line apiece.

Empty and still, he changes freely with all things; in Suchness and his original nature, he lets all be as it will.

空寂 is emptiness-and-quiescence, and 真如 is tathatā, "Suchness," the Buddhist term for reality just as it is. The logic of the couplet is worth having: because he rests in the unconditioned, he can change with anything and act without constraint (任為之, 為 wéi). Emptiness here is not blankness. It is what makes transformation possible — which is precisely the art he is about to teach.

A majestic body, long-lived as Heaven itself; through kalpa on kalpa, mind-illumined — a great master of the Dharma.

莊嚴 is the Buddhist "adorned, majestic," 劫 (jié) is a kalpa or world-age, 明心 is the illumined mind of enlightenment, and 大法師 is a great master of the Dharma. Count the Buddhist terms in this eight-line portrait and you will not find a Daoist one to match them. The man who teaches immortality in a grotto is painted, start to finish, as an enlightened Buddha.