解鎖之法 The Lock Opening Spell
卻就取出金箍棒，望門一指，使出那解鎖之法，那門就輕輕開了。急拽步出門站下，厲聲高叫道：「賽太歲，還我金聖娘娘來。」連叫兩三遍，驚動大小群妖，急急看處，前門開了。却就取出金箍棒，望门一指，使出那解锁之法，那门就轻轻开了。急拽步出门站下，厉声高叫道：「赛太岁，还我金圣娘娘来。」连叫两三遍，惊动大小群妖，急急看处，前门开了。
逐句解 Line by line
So he took out the gold-banded cudgel, pointed it at the door, brought out his lock-opening spell,
金箍棒 is the iron cudgel with the gold bands, the most famous weapon in Chinese fiction, and here it is being used as a key. 一 takes yì before the rising tone of 指.
and the door swung gently open.
Seven characters. 輕輕 is the doubled word for doing something softly — used of Wukong landing on the queen's hair, and of the sleep bug being set on a face, and now of a locked gate giving way.
He strode quickly out through the door, planted himself, and shouted at the top of his voice, "Rival of the Grand Year! Give me back the Golden Sage Queen!"
還 is huán, the verb — give back. 康熙 辵部十三畫 opens at 戸關切 · 胡關切, 𠀤音環, 說文 復也, 玉篇 反也, and adds 又償也, to repay; the everyday hái of still and yet is a later word the dictionary does not carry, and it is not what he is shouting. 拽 is read yè. Three old authorities agree and none of them knows the modern reading: 康熙 手部六畫 gives the character three bands and every one belongs to 曳 — 同抴, 拖也, 音曳, 引也 — with 正字通 calling it a corrupted form of that character outright; 洪武正韻 files it under 曳 at 以制切; and 中原音韻 groups it with 噎, 謁, 葉 and 燁, all of them yè-syllables. 拽步 is to stretch the stride, which is 引也 — and the novel uses the same verb elsewhere in 拽開步, 拽回步 and 拽杖, always for dragging or stretching.
He called two or three times running, which roused the fiends great and small; and when they hurried to look, the front gate stood open.
處 is chù, turning the verb before it into a moment — the point at which they looked.
The gold-banded cudgel opens a lock. That is worth sitting with for a second — the weapon that has fought armies and held up the sky is pointed at a door catch, and the door opens gently. Wukong has spent this entire chapter using enormous power to do very small things.
Then he ruins his own escape on purpose. He has the bells, the door is open, and nobody has seen him. He walks out, stops, and shouts the fiend's name until the household wakes up. The theft was never the point; the point is to get the queen out, and for that he needs the monster awake and outside.
還我金聖娘娘來 is the first straight demand anyone has made in this chapter. Everything up to here has been disguise, flattery, wine and lice. Now the disguise is off and the demand runs seven characters.