寄有家書 The Passport Returned, a Letter Revealed
國王見了，取本國玉寶，用了花押，遞與三藏。三藏謝了恩，收了文牒，又奏道：「貧僧一來倒換文牒，二來與陛下寄有家書。」國王大喜道：「有甚書？」三藏道：「陛下第三位公主娘娘，被碗子山波月洞黃袍妖攝將去，貧僧偶爾相遇，故寄書來也。」国王见了，取本国玉宝，用了花押，递与三藏。三藏谢了恩，收了文牒，又奏道：「贫僧一来倒换文牒，二来与陛下寄有家书。」国王大喜道：「有甚书？」三藏道：「陛下第三位公主娘娘，被碗子山波月洞黄袍妖摄将去，贫僧偶尔相遇，故寄书来也。」
逐句解 Line by line
When the king had read it, he took the treasure-seal of his own realm, affixed his signature, and handed it back to Tripitaka.
玉寶 = "the jade seal," the seal of state; 花押 = "a signature-monogram," the ruler's personal cipher. The renewal of the passport is thus completed with the Baoxiang seal added beside the nine of Tang.
Tripitaka gave thanks for the favor, put away the rescript, and then reported further: 'This humble monk came, first, to have the rescript renewed; and second, to deliver a family letter to Your Majesty.'
謝恩 = "to give thanks for [the sovereign's] grace"; 倒換文牒 (倒 = dào) = "to renew the travel-rescript." 家書 = "a family letter" — the one the captive princess entrusted to him in the cave.
Greatly pleased, the king said, 'What letter is this?'
有甚書 (甚 = shén, the interrogative) = "what letter is there?" The king's pleasure at the mention of a letter, before he knows its content, sharpens the grief to come.
Said Tripitaka, 'Your Majesty's Third Princess was carried off by the Yellow-Robe Ogre of the Wave-Moon Cave on Bowl Mountain. This humble monk chanced to meet with her, and so she has sent this letter by me.'
第三位公主娘娘 = "the Third Princess." 碗子山波月洞黃袍妖 names the demon and his lair, "the Yellow-Robe Ogre of the Wave-Moon Cave on Bowl Mountain." 攝將去 (將 = jiāng, the coverb) = "abducted away"; 相遇 (相 = xiāng) = "met by chance."
The scene pivots on the second of Tripitaka's two errands. The first, the renewal of his passport, is dispatched in a sentence — seal, signature, handing-back — the routine courtesy of one realm to a traveler from another. But the letter is another matter, and the novel is careful to stage the king's pleasure before he knows its contents: "What letter is this?" he asks, greatly pleased, and the reader, who knows, feels the coming grief gather behind the question.
Tripitaka is here the unwitting bearer of catastrophe. He delivers, with a monk's mild courtesy, the news that will shatter a court: that the princess lost thirteen years ago is alive, a demon's captive and a demon's wife. The chance meeting in the cave, undertaken as a small kindness, now sets in motion the whole machinery of a royal rescue — and, with it, the trouble that will fall upon the pilgrims themselves.