好殺 A Fierce Clash
他兩個也不論親情，一齊變臉，各使神通，跳在雲端裡，好殺：他两个也不论亲情，一齐变脸，各使神通，跳在云端里，好杀：
逐句解 Line by line
The two of them, kinship set aside, changed countenance as one, each loosed his powers, and sprang up into the clouds — a fierce fight it was:
好殺, "a fierce fight it was," is the cue: a formal descriptive set-piece is about to start. Ming novels announce their verse rather than sliding into it, and the cue belongs to the prose. 不論親情, kinship set aside, is the narrator closing the argument of the last three passages in four characters.
The Pilgrim's name rang great; the demon king's skill was strong.
The opening pair states the two powers: one has the reputation, the other has the skill. 強 is qiáng, strong, not the qiǎng that means to force. It is a fair assessment, and the fight will bear it out.
The one held level his gold-banded cudgel; the other thrust straight his fire-tipped spear.
Weapon against weapon, held in parallel. 橫舉 is holding the cudgel level and crosswise, guarding; 直挺 is driving the spear straight, attacking. The grammar of the couplet puts them side by side so you see the guard and the thrust at once.
Spat mist to veil the Three Realms; blew cloud to light the four quarters.
The scale jumps. 三界, the Three Realms, is the Buddhist division of everything that exists into the realm of desire, the realm of form, and the formless realm -- so "veiled the Three Realms" means the mist covered all of it. 四方 is the four directions. Two fighters, and the weather system of the universe.
A whole sky of killing air, a savage roar of voices; sun, moon, and stars showed no light.
殺氣 is the killing air, the atmosphere of slaughter, imagined as something that fills a sky the way weather does. The second line does what these set-pieces always do at their peak and puts out the lights: 日月星辰不見光, sun and moon and stars gave no light. 不 takes bú before the falling tone of 見.
In speech, no yielding; in temper, both perverse and crossed.
From the cosmic back down to the two of them, and to their tempers. No yielding in what they say, and both crossed and contrary in what they feel. 乖張 guāi zhāng means perverse, set at odds -- people who will not be reasoned with.
That one, wronging his heart, cast courtesy aside; this one, altering his face, held to no bond or rule.
那一個…這一個, that one and this one, is the standard way these pieces alternate between the fighters. 綱常 is a heavy word to reach for here: it names the fundamental bonds of Confucian society, the relationships that hold the world together. Charging each fighter with having none of them raises a brawl into a breach of the moral order, which is a joke and is also, given that they genuinely are uncle and nephew by oath, half serious.
The cudgel's guard — its might towering; the spear's onset — its wild nature raging.
威風長: 長 is read cháng, meaning towering or lofty, not the zhǎn that means to grow. It has to be -- the piece rhymes on an -áng sound and 長 sits in the rhyme slot, paired with 狂 kuáng, raging, at the end of the matching line. The rhyme picks the reading.
The one, a true Great Sage of Primal Unity; the other, the Boy of Good Wealth bound for the true fruit.
The most interesting couplet in the piece, and easy to skate past. Wukong is called 混元真大聖, Great Sage of Primal Unity. Red Boy is called 正果善財郎 -- and 善財 is Sudhana, the Boy of Good Wealth, a famous pilgrim-disciple from Buddhist scripture. That is not who Red Boy is. It is who he is going to be: in the next chapter Guanyin subdues him and takes him as her 善財童子. The narrator, mid-fight, is calling the demon by the name he will earn after losing.
The two strove with all their strength for mastery — and all for the Tang Monk, who goes to bow before the Dharma-King.
The closing lines pull back and put the fight in its place. All this straining for mastery is 只為唐僧拜法王 -- only so the Tang Monk may go and bow before the Dharma-King. 為 is wèi, for the sake of. The duel is not the point of anything; the journey is.
On the surface this is a standard combat set-piece: matched weapons, blackened heavens, both parties accused of having no manners. The novel has dozens of these and they are enjoyable in the way a well-choreographed fight scene is enjoyable.
Two lines do more than that. Wukong is named Great Sage of Primal Unity, and Red Boy is named 正果善財郎, the Boy of Good Wealth bound for the true fruit. 善財 is Sudhana, and in Chapter 42 Guanyin will subdue this demon and take him into her service under exactly that name. So the narrator, in the middle of the battle, is already calling him by his future title. It is a small act of spoiling, and it is deliberate: the reader is being told that the outcome is not in doubt, only the cost.
The last couplet does the same work from the other end, reminding you that two immortals wrecking the sky are doing it so that a nervous monk can complete a walk to India. The novel is fond of that deflation.