放火之輩 The Sage Accused of Arson
土地說：「大力王即牛魔王也。」行者道：「這山本是牛魔王放的火，假名火焰山？」土地道：「不是，不是。大聖若肯赦小神之罪，方敢直言。」行者道：「你有何罪？直說無妨。」土地道：「這火原是大聖放的。」行者怒道：「我在那裡？你這等亂談。我可是放火之輩？」土地说：「大力王即牛魔王也。」行者道：「这山本是牛魔王放的火，假名火焰山？」土地道：「不是，不是。大圣若肯赦小神之罪，方敢直言。」行者道：「你有何罪？直说无妨。」土地道：「这火原是大圣放的。」行者怒道：「我在那里？你这等乱谈。我可是放火之辈？」
逐句解 Line by line
The Local Spirit said, "The King of Great Strength is none other than the Bull Demon King."
The chapter opens in mid-dialogue, on the Local Spirit's answer to the question the previous chapter closed upon; there is no 話說 or 卻說 at the head. 即 is the copula of flat identification: not a comparison but an equation.
Pilgrim said, "Then the fire on this mountain was set by the Bull Demon King, and the name Mountain of Flames is a false one?"
假名 here is jiǎ, false or assumed, not jià a leave of absence. Pilgrim's guess is that the name conceals an agent — which is right in form and wrong in person.
"No, no," said the Local Spirit. "If the Great Sage will pardon this humble deity's offence, only then would I dare speak plainly."
小神 is the self-abasing form a minor deity uses before a superior. The Local Spirit asks pardon before naming the offence, which is itself the tell: the offence is one the Great Sage will not want to hear.
Pilgrim said, "What offence have you? Speak out; there is no harm in it."
Two clauses the source separates with a question mark are rejoined here as one speaker turn.
The Local Spirit said, "This fire was, at its origin, set by the Great Sage himself."
原 carries the weight of the sentence: not that the Sage tends the fire now, but that he is its origin.
Pilgrim said in anger, "Where was I? You talk such nonsense. Am I the sort of creature who sets fires?"
那 is nǎ here, the rhetorical interrogative, not the deictic nà — Pilgrim is not pointing at a place but denying he was ever at one. pypinyin bakes nà at this site. 之輩 is dismissive: not a person but a class of person.
The chapter begins with no formula at all. Where a reader expects 話說 or 卻說 to reopen the narration, the text simply resumes the Local Spirit in mid-sentence, answering the question that closed the previous chapter. The effect is that of a curtain that never fell: the interrogation on the Mountain of Flames has been running continuously, and the reader is returned to it without ceremony.
The exchange is built as a slow reversal. Pilgrim proposes a culprit — the Bull Demon King, whose name he has just been given — and the Local Spirit refuses it twice before asking, in the language of a minor official petitioning a great one, for pardon in advance. Only then does he name the arsonist, and the arsonist is the interrogator. The comedy is exact: the Great Sage has spent the whole of the previous chapter demanding to know who is responsible for an obstacle, and the answer is that he is.
Pilgrim's indignation is the joke's second half. 我可是放火之輩 — am I the sort who sets fires — is a rhetorical question with an unambiguous answer, and the novel has spent seven chapters establishing it. The reader supplies what Pilgrim will not. This is the structural principle the whole Mountain of Flames episode turns upon: the obstacle in the pilgrims' path is not an accident of geography but a debt, and the debtor is the one being obstructed.