取真經 Sent To Fetch True Scriptures
三藏道：「是東土大唐駕下差往西方天竺國大雷音寺拜活佛取真經的。」國王道：「老師遠來，為何在這櫃裡安歇？」三藏道：「是东土大唐驾下差往西方天竺国大雷音寺拜活佛取真经的。」国王道：「老师远来，为何在这柜里安歇？」
逐句解 Line by line
Tripitaka said, "We are sent by the throne of the Great Tang in the Land of the East to the Great Thunderclap Monastery in the Western Country of India, to bow before the Living Buddha and fetch the true scriptures."
The whole pilgrimage in one breath, and Tripitaka can deliver it in his sleep by now — he has recited some version of it at every border on the road. 天竺 is the old Chinese name for India; 大雷音寺, Great Thunderclap, is the Buddha's seat and the journey's destination. 駕下, beneath the imperial carriage, means by the emperor's own commission.
The king said, "Master, you have come far. Why were you lodging in this chest?"
The obvious question, and a fair one. 為 is wèi here, for what reason, as against the wéi of taking something as something, which this chapter uses several times elsewhere. 安歇 is a polite word for resting, and using it of a stolen box is the king being courteous about something quite strange.
Tripitaka's set speech is a passport. Wherever the road takes him, the same sentence comes out, naming the sending power, the destination and the errand, and it has kept him alive at more than one frontier.
The king's question is the polite version of what everyone in the hall is thinking. He has just bowed to four strangers found inside recovered stolen property, and he would still rather like to know why they were in there.