六字真言 The Seal of Six Syllables
如來又稱謝了，叫阿儺、迦葉將各所獻之物一一收起，方向玉帝前謝宴。眾各酩酊。只見個巡視靈官來報道：「那大聖伸出頭來了。」佛祖道：「不妨，不妨。」袖中只取出一張帖子，上有六個金字：「唵、嘛、呢、叭、咪、吽。」遞與阿儺，叫貼在那山頂上。這尊者即領帖子，拿出天門，到那五行山頂上，緊緊的貼在一塊四方石上。那座山即生根合縫，可運用呼吸之氣，手兒爬出，可以搖掙搖掙。如来又称谢了，叫阿傩、迦叶将各所献之物一一收起，方向玉帝前谢宴。众各酩酊。只见个巡视灵官来报道：「那大圣伸出头来了。」佛祖道：「不妨，不妨。」袖中只取出一张帖子，上有六个金字：「唵、嘛、呢、叭、咪、吽。」递与阿傩，叫贴在那山顶上。这尊者即领帖子，拿出天门，到那五行山顶上，紧紧的贴在一块四方石上。那座山即生根合缝，可运用呼吸之气，手儿爬出，可以摇挣摇挣。
逐句解 Line by line
The Tathāgata again gave thanks, bade Ānanda and Kāśyapa gather up one by one the things that had been offered, and then before the Jade Emperor gave thanks for the banquet.
將各所獻之物 is 將 as jiāng. 一一 repays a look: the first 一 shifts to yì, the second keeps its own tone — one by one. The courtesies are winding down. The evening's real business has not been done yet.
All were dead drunk. Then a Patrolling Officer came to report: "That Great Sage has poked his head out." The Buddha said: "No matter, no matter."
酩酊 (mǐng dǐng) is blind drunk; both characters carry the wine element, which is a neat piece of visual design. Into all that comes the report that the prisoner has got his head out. The Buddha says 不妨, no harm, twice, and does not put down his cup. The unconcern tells you everything about what is coming.
From his sleeve he took out a single slip of paper, on which were six golden words: "Oṃ, ma, ṇi, pad, me, hūṃ." He handed it to Ānanda and told him to paste it on the mountain's summit.
唵嘛呢叭咪吽 (ǎn ma ne bā mī hōng) is the Chinese spelling-out of Oṃ maṇi padme hūṃ, the six-syllable invocation of Avalokiteśvara and the most repeated mantra in Mahāyāna Buddhism. 一張 takes yì before zhāng (level tone). Note what the seal actually is. Not a chain and not a lid — a slip of paper with sound written on it.
The venerable one took the slip, carried it out of the Heaven-gate, came to the summit of the Mountain of Five Phases, and pasted it fast upon a square stone.
尊者 (zūn zhě) is the venerable one, meaning Ānanda. 五行山 keeps 行 as xíng. 一塊 takes yí before kuài (falling tone). That completes the picture: Five Phases below, six syllables above, one square stone between them.
That mountain at once took root and sealed its seams; yet he could still draw breath, and work a hand out to scrabble and wriggle a little.
生根合縫 — it grew roots and closed its seams. The paper does what the whole weight of the mountain could not, and the prison becomes airtight. Except that it does not, quite. He can still draw breath, and work one hand out to scrabble with. 搖掙 keeps 掙 as zhèng, to struggle. That small allowance is deliberate, and it is what keeps him alive for a rescue five hundred years off.
The chapter's final instrument is not force but a mantra. The Buddha takes a paper slip from his sleeve bearing six golden words — 唵嘛呢叭咪吽, the transliteration of Oṃ maṇi padme hūṃ, the six-syllable invocation of Avalokiteśvara — and has it pasted on the mountain's summit. At once the mountain takes root and seals its seams. What holds the monkey, in the end, is sacred sound: the spoken Dharma turned into a lock.
This completes a deliberate progression. Heaven tried metal, fire and thunder, and failed. The Buddha used first his palm (the encompassing real), then the mountain (the Five Phases, cosmic order), and finally the mantra (the Dharma as sound). Each is subtler than the last and each is more decisive. There is a fitness in it: the unbound 心猿, a creature of pure restless energy, is fixed at last not by a heavier weight but by a word.
The crucial detail is that the seal is incomplete. The monkey can still breathe and work a hand out to scrabble and wriggle a little (搖掙搖掙). This is mercy dressed up as oversight. A perfect tomb would end the story; a breathing prison keeps the captive for the redemption to come. As Anthony C. Yu emphasizes, the five hundred years under the mountain are punishment and refinement at once — and the small gap left for breath is the story's promise that this 心猿, stilled but not extinguished, will live to be freed and walk the pilgrim road. The next chapter begins the long preparation for that release.