躬身施禮 Zhang Ziyang Presents Himself
行者上前迎住道：「張紫陽何往？」紫陽真人直至殿前，躬身施禮道：「大聖，小仙張伯端起手。」行者答禮道：「你從何來？」行者上前迎住道：「张紫阳何往？」紫阳真人直至殿前，躬身施礼道：「大圣，小仙张伯端起手。」行者答礼道：「你从何来？」
逐句解 Line by line
Pilgrim came forward to meet him and said, "Zhang Ziyang — where are you bound?"
Wukong knows him on sight and by name. 紫陽, Purple Sunlight, is the honorific style the verse gave as 紫雲仙 a moment ago; the two are the same person.
The Perfected Man Ziyang came straight to the front of the hall, bowed and paid his respects: "Great Sage — the humble immortal Zhang Boduan salutes you."
張伯端 is a real person: a Song adept of inner alchemy, author of a famous treatise on the subject, and honoured as founder of the Southern Lineage. 真人, Perfected Man, is his Daoist rank. 起手 is to raise the hands in salute.
Pilgrim returned the courtesy and said, "Where have you come from?"
Nine characters, carrying both its own attribution and its own closing quotation mark, so it stands alone. 答禮 is to return a bow — Wukong, who has spent the chapter insulting people, observes the form exactly.
The novel drops a real historical person into the throne room. Zhang Boduan, styled Ziyang, was a Song-dynasty writer on inner alchemy whose treatise became foundational for the Southern Lineage of the Daoist internal tradition — and here he turns up in a palace in a fictional kingdom, wearing a raincape, to explain a plot device.
The exchange is entirely ceremonial and takes three segments. He comes to the front of the hall, bows, gives his name; Wukong returns the bow and asks where he has come from. Both of them observe the etiquette to the letter, which is not how Wukong has behaved with anybody else in this chapter.
紫陽 and 紫雲仙 are the same figure under two names — the verse called him the Purple Cloud Immortal and Wukong greets him as Purple Sunlight. The reader is expected to have made the connection from the portrait alone.