釘鈀勢亂 The Rake Is Losing Ground
他的真身出個神，跳在空中觀看，但見那獃子被怪圍繞，釘鈀勢亂，漸漸的難敵。行者忍不住，按落雲頭，厲聲高叫道：「八戒不要忙，老孫來了。」他的真身出个神，跳在空中观看，但见那呆子被怪围绕，钉钯势乱，渐渐的难敌。行者忍不住，按落云头，厉声高叫道：「八戒不要忙，老孙来了。」
逐句解 Line by line
His true body slipped out in spirit, sprang up into the air to watch, and saw the blockhead ringed about by the monsters, the muckrake's movements coming apart, and little by little the odds against him.
出個神 is the real self stepping out while the copy stays. 勢亂 — the form falling into disorder — answers the battle poem exactly: there the rake was casting its practised sequences, and here the sequences are breaking down. 漸漸的, little by little, is the novel refusing to let it be sudden.
Pilgrim could not hold back. He pressed his cloud down and called out at the top of his voice, "Bajie, do not fret. Old Sun is here."
忍不住 — could not bear it — is the same verb that described Bajie springing out of the chest at the top of the chapter. Whatever the plan was, watching it work is more than he can stand.
The plan required Bajie to be captured. Pilgrim watches the capture begin and cannot sit through it, which is the most generous thing the chapter says about him.
He does not fight. He shouts, and the shout is a name — his own. That turns out to be the whole intervention.