善惡之報 Good and Evil
行者禁不得疼痛，跪於路傍，只叫：「莫念，莫念，有話快說了罷。」唐僧道：「猴頭，還有甚說話？出家人行善，如春園之草，不見其長，日有所增；行惡之人，如磨刀之石，不見其損，日有所虧。你在這荒郊野外，一連打死三人，還是無人檢舉，沒有對頭；倘到城市之中，人煙湊集之所，你拿了那哭喪棒，一時不知好歹，亂打起人來，撞出大禍，教我怎的脫身？你回去罷。」行者禁不得疼痛，跪于路傍，只叫：「莫念，莫念，有话快说了罢。」唐僧道：「猴头，还有甚说话？出家人行善，如春园之草，不见其长，日有所增；行恶之人，如磨刀之石，不见其损，日有所亏。你在这荒郊野外，一连打死三人，还是无人检举，没有对头；倘到城市之中，人烟凑集之所，你拿了那哭丧棒，一时不知好歹，乱打起人来，撞出大祸，教我怎的脱身？你回去罢。」
逐句解 Line by line
Pilgrim, unable to bear the pain, knelt in the road and only cried: "Stop, stop! If you have something to say, say it quick, and be done."
On his knees again. The scene from the first recitation is playing a second time in almost the same words — stop, stop, say what you have to say — which is how this chapter shows a groove wearing deeper. (禁不得 takes the toneless de.)
The Tang Monk said, "Monkey-head, what more have you to say?
猴頭, monkey-head, again. And the question is not an invitation: what follows is a lecture, not a hearing. (還 is hái; 甚 is shén.)
"A monk who does good is like the grass of a spring garden: you do not see it grow, yet day by day it increases.
This is the most quoted thing in the chapter, and it deserves to be. Doing good is like grass in a spring garden — you never catch it growing, and every day there is more of it. Note the reading: 長 here is zhǎng, "to grow", not cháng, "long".
"A person who does evil is like a whetstone for a knife: you do not see it wear, yet day by day it wastes away."
And the answering half, which is better still: doing evil is like the stone you sharpen knives on. You never catch it wearing away, and every day there is less of it. Two images, both about changes too slow to watch. It is genuinely fine moral teaching — and it is being delivered to a man kneeling in the road with a metal band tightening on his skull, for the offence of having saved the speaker's life.
"Out here in this wild waste, you've beaten three people to death in a row, and still there's no one to report it, no plaintiff against you;
And here the argument changes character completely. 檢舉 is to lay information against somebody, to report them to the authorities; 對頭 is the opposing party in a lawsuit. The elder has stopped talking about virtue and started talking about whether they will be caught. (還 is hái.)
"but should we come to a city, a place thick with people and hearth-smoke, and you take up that mourner's-club of yours and, in a fit of not knowing good from ill, fall to beating people at random and stir up some great calamity — how am I to get myself clear?
哭喪棒 — the mourner's staff, the stick a chief mourner leans on at a funeral — is a wonderfully nasty name for the cudgel, and the elder has clearly been saving it. Then the real fear: in a town, with people about, this creature might start swinging, and I should never get clear of it. 教我怎的脫身 — how am I to get myself out? Not how would I bear the guilt. How would I get away. (那 points, nà; 中 is zhōng; 教 is jiào.)
"Go back where you came from."
你回去罷 is word for word the first dismissal. The second was the same phrase a syllable shorter, 你去罷. He will use the full form once more before the chapter ends. The groove is now deep enough that he does not have to think about it.
Tripitaka's response to the exposed demon is not gratitude but a lecture, and the lecture is the most quoted passage in the chapter: goodness is like spring grass, growing unseen but always increasing; evil is like a whetstone, wearing unseen but always wasting. It is real Buddhist moral teaching, beautifully phrased — and, aimed at the disciple who has just destroyed a fiend to save him, catastrophically misapplied.
Beneath the homily runs something a good deal more worldly. The elder frets that out here the killings go unreported, but that in a crowded city the cudgel might bring calamity down on them all — and the question he asks is how he would get clear, not how he would live with it. It is a strikingly self-protective note, and it shows the dismissal is driven quite as much by his own dread as by any principle.
The third dismissal repeats the first word for word, the second having been the same phrase shorn of a syllable. The repetition is the point: the pattern has hardened past the reach of plea or evidence. Where the earlier kneeling appeals reversed it, this one comes after the truth has been shown and refused, so it will not be undone. It runs on instead to the written dismissal and the parting.