西江月 A Chapter-Opening Lyric
詩曰：诗曰：
逐句解 Line by line
A poem runs:
Before a word of story, a poem. That is normal for this novel, and the two characters 詩曰 ("a poem runs") are the signal that one is coming. What follows is not loose verse but a set-piece lyric (詞) written to the fixed tune-pattern 西江月, "Moon over the West River" — new words fitted to a tune the audience already knew, much as a songwriter today writes fresh lyrics over a familiar melody. Its content is the preachy, inner-alchemy verse the novel keeps borrowing from the 悟真篇 line of Daoist poetry.
Idle fancies need not be forcibly quelled; / as for suchness — why must it be sought at all?
The lyric opens on a paradox that Chan Buddhists and inner-alchemy Daoists both liked: you cannot bully your way to enlightenment, and you cannot go shopping for it either. 妄想, stray or deluded thinking, is set against 真如 (tathatā, "suchness" — reality exactly as it is). 強 is qiǎng here, "by force." Crushing the delusion and chasing the suchness both fail, because both are still somebody trying.
The primal self-nature is cultivated in the Buddha's presence; / do delusion and awakening lie the one before the other?
自性 (svabhāva, "self-nature") is held to contain buddhahood already, so the cultivating happens "before the Buddha" who turns out to be your own nature. The second line then refuses to put 迷 (straying) and 悟 (waking) in any running order: waking is a turn within the same nature, not the next item on a list.
Awaken, and in a kṣaṇa one attains the right; / stray, and through myriad kalpas one sinks and drifts.
Now the lyric puts a clock on the two states. 悟 is timed in a 剎那 (kṣaṇa, the briefest instant Buddhist thought will name); 迷 in 萬劫, ten thousand kalpas. Waking takes no time at all; straying takes forever. 成正 is to attain the correct fruit, 沉流 to sink in the stream of saṃsāra.
Could a single thought accord with true cultivation, / it would extinguish sins numberless as Ganges sands.
The pay-off. 一念 — one instant of mind — brought into accord with 真修, true cultivation, is enough to dissolve every stain. 恆沙 (Gangā-vālukā, "sands of the Ganges") is the standard Buddhist way of saying "more than anyone could ever count"; 罪垢 is sins-and-grime. The lyric ends where this school always ends, on the single thought that does the whole job.
The chapter is prefaced, in the storyteller's manner, with a 西江月 lyric that mixes its sources without apology. The vocabulary is Buddhist throughout — 真如, 自性, 剎那, 萬劫, 恆沙, 罪垢 — but the idea running underneath it, that one accordant thought (一念) collapses the entire labour of cultivation, belongs to the Quanzhen and 悟真篇 tradition of inner-alchemical verse that this novel absorbs at every turn. The teaching is a quiet one: do not beat the delusion down, do not run after the suchness, because both moves misread a nature that already is what it is looking for.
Put here, the lyric works as an ironic overture. The story it introduces shows the pilgrims doing exactly what the verse warns against — 迷, straying, rather than 悟, waking. Tripitaka is tied to a post and weeping; Eight Rules and Sha Monk cannot win their fight. The gap between a poem that says awakening takes one instant and a journey that takes a hundred chapters is the novel's running joke and its deepest subject at the same time.