弄巧翻成拙 Cleverness Turned To Clumsiness
妖王道：「正是，正是，見得有理。」叫：「小的們，仔細搜求防避，切莫開門放出走了。」這才是個有分教：妖王道：「正是，正是，见得有理。」叫：「小的们，仔细搜求防避，切莫开门放出走了。」这才是个有分教：
逐句解 Line by line
The fiend king said: "Just so, just so. That is reasonably seen."
見得 takes dé, the perceiving-verb reading. Just so, doubled — he accepts the bear's account entire and adds nothing at all to it.
He called: "You little ones, search and guard with care. On no account open the gate and let him out."
仔 is zǐ, the third in this passage. The order is the same one he gave before the bear spoke, with the gate clause added — so knowing exactly who the thief is has changed nothing he can actually do about it.
And this is what it comes to:
有分教 is the storyteller's formula for what a situation is about to lead to. The announcement sits at the tail of its own prose sentence and cannot be parted from the couplet it opens.
Playing clever turned to playing the fool; the sport turned out to be earnest.
為 is wéi, to become — not the wèi of on account of. Five characters and five, with a single rhyme position and nothing to answer it: the line ends on zhēn against a midpoint of zhuō.
The demon agrees with the bear in four characters and then repeats the order he had already given. He now knows exactly who is loose in his mountain and it makes no difference to his instructions: search carefully, keep the gate shut. Being right has bought him nothing.
The couplet closes on a proverb, and the proverb is about Wukong. Playing clever turned to playing the fool — the set phrase is still current Chinese for an attempt that backfires, and the line splits it with an extra character meaning turned right over. What turned it was the cotton wool.
The second line is the sharper of the two. The sport turned out to be earnest: he came into this cave in a costume, made a joke of a dead man's name, and answered a gorilla's greeting with two characters he had not chosen. The performance has stopped being one.