東天門外 Outside the Eastern Gate
好行者，急忙駕觔斗雲，須臾到東天門外。忽見增長天王當面作禮道：「大聖何往？」行者道：「因保唐僧西方取經，路遇魔障纏身，要到光明宮見昴日星官走走。」忽又見陶、張、辛、鄧四大元帥，也問何往。行者道：「要尋昴日星官去降妖救師。」四元帥道：「星官今早奉玉帝旨意，上觀星臺巡察去了。」行者道：「可有這話？」辛天君道：「小將等與他同下斗牛宮，豈敢說假？」陶天君道：「今已許久，或將回矣。大聖還先去光明宮，如未回，再去觀星臺可也。」好行者，急忙驾觔斗云，须臾到东天门外。忽见增长天王当面作礼道：「大圣何往？」行者道：「因保唐僧西方取经，路遇魔障缠身，要到光明宫见昴日星官走走。」忽又见陶、张、辛、邓四大元帅，也问何往。行者道：「要寻昴日星官去降妖救师。」四元帅道：「星官今早奉玉帝旨意，上观星台巡察去了。」行者道：「可有这话？」辛天君道：「小将等与他同下斗牛宫，岂敢说假？」陶天君道：「今已许久，或将回矣。大圣还先去光明宫，如未回，再去观星台可也。」
逐句解 Line by line
Splendid Pilgrim! He mounted his cloud-somersault in haste, and in a moment was outside the Eastern Gate of Heaven.
觔 is always jīn, and 觔斗 takes 斗 as dǒu — the somersault, not the dòu of combat. 須臾 is the shortest conventional stretch of time, roughly "in the time it takes to say so".
Of a sudden he saw the Heavenly King of Increase, who saluted him face to face and said, “Where is the Great Sage bound?”
增長天王 is one of the four Heavenly Kings who guard the quarters — his Sanskrit name is Virūḍhaka, and the Chinese renders it by sense rather than by sound. 長 is zhǎng. 當面 takes 當 as dāng.
Pilgrim said, “Escorting the Tang Monk westward for the scriptures, we have met a demon-obstruction on the road that has us entangled. I want to go to the Palace of Radiance and look in on the Star Officer of the Mao mansion.”
魔障 is an obstruction of demonic origin — a term of art in Buddhist writing for anything that gets in the way of practice. 走走 doubles the verb to make it casual: "look in on".
Then of a sudden he saw the four great Marshals Tao, Zhang, Xin and Deng, who also asked where he was bound.
The four are the thunder-marshals of the celestial civil service.
Pilgrim said, “I am seeking the Star Officer of the Mao mansion, to go and subdue a fiend and save my master.”
降妖 takes 降 as xiáng, to subdue; the jiàng of coming down would be wrong here.
The four Marshals said, “The Star Officer received the Jade Emperor's command this morning and has gone up to the Star-Watching Terrace on his rounds.”
奉玉帝旨意 is the formula for receiving an order from the throne. 巡察 is a tour of inspection, and heaven runs them exactly as the earthly bureaucracy does — the officer Pilgrim needs is out on his rounds.
Pilgrim said, “Is that so?”
可有這話 is a bare expression of doubt: "is that so?"
The Heavenly Lord Xin said, “We lesser officers came down from the Palace of the Dipper and the Ox in his own company. Should we dare speak falsely?”
小將 takes 將 as the rank jiàng, not the handling word jiāng — as with the divine generals earlier in the chapter, the character is a head noun. 斗牛宮 takes 斗 as dǒu, agreeing with Pilgrim's own account of being taken there to be beheaded.
The Heavenly Lord Tao said, “It has been a good while now; he may be about to return. Let the Great Sage go first to the Palace of Radiance, and if he has not come back, go on then to the Star-Watching Terrace.”
或將回矣 takes 將 as the adverb jiāng, "about to" — a different reading from the rank 將 one line above, and the two stand a few characters apart.
Heaven in this novel is a civil service, and the passage is almost entirely procedural. Pilgrim is stopped at the gate by the Heavenly King on duty, who asks his business; stopped again by four marshals, who ask the same; told that the officer he wants is out, having received an imperial order that morning and gone up to the Star-Watching Terrace on his rounds; and advised where to wait and where to try next if the first attempt fails. Nothing supernatural happens at all.
The Great Sage moves through this apparatus as a petitioner, answering each challenge civilly and taking directions. It is worth remembering what he once did to this same establishment: he fought its armies, wrecked its banquet, and was hauled off to the Palace of the Dipper and the Ox to be executed — the very palace the Heavenly Lord Xin now mentions in passing as the place he and the Star Officer came down from together. Nobody alludes to any of it. The novel's long joke about Pilgrim's rehabilitation is that heaven has simply absorbed him into its paperwork.
The one flash of feeling comes from Xin, who is asked 可有這話 — is that so? — and takes it as an insult. 豈敢說假, should we dare speak falsely? The indignation of a middle-ranking official whose word has been doubted is caught exactly, and it is the most human moment in a scene otherwise made entirely of protocol.