結為兄妹 Sworn Brother And Sisters
行者躬身道：「女菩薩息怒。我本是東土大唐欽差御弟唐三藏大徒弟孫悟空行者。因往西天，行過黃花觀歇馬。那觀中道士，不知是個甚麼妖精，他與七個蜘蛛精結為兄妹。行者躬身道：「女菩萨息怒。我本是东土大唐钦差御弟唐三藏大徒弟孙悟空行者。因往西天，行过黄花观歇马。那观中道士，不知是个甚么妖精，他与七个蜘蛛精结为兄妹。
逐句解 Line by line
Pilgrim bowed. "Lady bodhisattva, let your anger rest."
息怒, let anger rest, is the same set formula the seven spider-women used on their elder brother a few thousand characters ago. It is what you say to somebody senior or offended, and Pilgrim is bowing to a stranger on a road.
"I am the senior disciple of Tripitaka of Tang, the imperial commissioner and sworn brother of the Emperor of the Great Tang in the Land of the East — Sun Wukong, called Pilgrim."
⚠ 差 is chāi, dispatched on official business, and this is the third and last of the chapter's three. 欽差 is an imperial commissioner — a man carrying the emperor's own warrant — and 御弟, imperial younger brother, is the honorific the Tang emperor gave Tripitaka. Twenty-two characters to say who he is, and nineteen of them are somebody else's titles.
"On our way to the Western Heaven we passed the Yellow Flower Abbey and stopped to rest the horse."
觀 is guàn, the abbey. 歇馬, resting the horse, is the whole of what they meant to do there — and it is worth remembering that resting the animals was Sha Monk's reason for going in at all.
"The Daoist in that abbey — I do not know what sort of monster he is — has sworn brotherhood with seven spider spirits."
⚠ 為 is wéi here, to become or be constituted as: 結為兄妹, bound into brother and sisters. Not the wèi of for-the-sake-of that appeared twice in the last passage. The character is one of the corpus's most reliable splits and it turns entirely on whether it means "be" or "for".
Pilgrim gives his credentials before his story, and the credentials take longer. Imperial commissioner, sworn brother of the emperor, senior disciple, Sun Wukong, Pilgrim — it is a calling card, and it is doing a specific job: establishing that the person weeping in front of her is not a vagrant with a grudge.
The detail he gets wrong is the interesting one. He tells her the Daoist and the spiders are 結為兄妹, sworn brother and sisters — an oath-bond, the kind sworn between unrelated people. The text told us the truth 3,782 characters earlier and it is different: 同堂學藝, they studied under one master. Pilgrim is reconstructing from evidence and getting the relationship category wrong.
It hardly matters to him and it matters a good deal to the reader, because the difference is exactly what the chapter turned on. A sworn brother might have traded seven lives for a prize. A fellow student did, and then could not bear to look at the bodies.