教勸那廝 Persuade the Man to Goodness
行者將米山、麵山、金鎖之事說了一遍，道：「果依你言，不肯傳旨。適間天師送我，教勸那廝歸善，即福原也。」遂相別，降雲下界。行者将米山、面山、金锁之事说了一遍，道：「果依你言，不肯传旨。适间天师送我，教劝那厮归善，即福原也。」遂相别，降云下界。
逐句解 Line by line
Pilgrim told over the whole business of the rice mountain, the flour mountain and the golden lock, and said, "It was just as you told me. He would not issue the edict.
果依你言 — it turned out just as you said. Pilgrim gives the gatekeeper the credit without being asked to, which is not a thing the monkey of the early chapters would have done.
"Just now the Preceptors saw me out, and told me to persuade the fellow to turn to goodness — that being the very source of good fortune."
那廝, that fellow — Pilgrim has picked up heaven's contemptuous word for the prefect and is using it himself, having met the man and seen him bow in the street. 福原 is the root or source of good fortune.
So they took leave of each other, and he brought his cloud down to the world below.
降雲下界, lowering the cloud to the world below, closes the heavenly excursion in five characters. The chapter now has everything it needs and only one thing left to do.
Pilgrim goes down carrying an instruction rather than an edict, and the difference is the whole point of the journey he has just made.
One small thing is worth noticing in his report. He calls the prefect that fellow — heaven's word, picked up on the way through. He has met Shangguan. He has been bowed to in the street by him and given the seat of honour. And he still repeats the celestial contempt without apparently hearing himself do it, which sets up the scene waiting for him at the bottom of the cloud, where he is about to shout at a man he is supposed to be persuading.