權借高衙 Borrowing Your Office For A Rest
三藏合掌道：「貧僧乃東土大唐駕下差往西天取經者。今到寶方，不敢私過，有關文欲倒驗放行，權借高衙暫歇。」三藏合掌道：「贫僧乃东土大唐驾下差往西天取经者。今到宝方，不敢私过，有关文欲倒验放行，权借高衙暂歇。」
逐句解 Line by line
Tripitaka joined his palms and said, "This poor monk is one sent by the throne of the Great Tang in the Land of the East to fetch scriptures from the Western Heaven.
差 is chāi, to send somebody on official business. The default reading is chà, which belongs to falling short or going wrong, and the sealed chapters keep the two apart in exactly this way.
"Come now to your precious realm, I dare not pass through unannounced. I have a travel rescript I would have endorsed and examined so that we may go on, and I would borrow your honourable office to rest a while."
倒 is dǎo again — 倒驗 pairs the exchanging of the document with its inspection. 私過 is to pass through privately, without presenting oneself, and it is the thing he is careful to disclaim.
This is the formula Tripitaka uses at every border, and it is worth noticing how much of it is deference. He calls himself poor, names his errand, disclaims any wish to slip through unannounced, and asks to borrow rather than to be given.
不敢私過 is the load-bearing phrase. Passing through a kingdom without presenting the rescript would be an offence, and the whole shape of these episodes rests on the pilgrims being scrupulous about a piece of paper while being casual about almost everything else.