叫龍現身 Summon the Dragons to Show
那國師若能叫得龍王現身，就算他的功勞。」國王大喜道：「寡人做了二十三年皇帝，更不曾看見活龍是怎麼模樣。你兩家各顯法力，不論僧道，但叫得來的，就是有功；叫不出的，有罪。」那国师若能叫得龙王现身，就算他的功劳。」国王大喜道：「寡人做了二十三年皇帝，更不曾看见活龙是怎么模样。你两家各显法力，不论僧道，但叫得来的，就是有功；叫不出的，有罪。」
逐句解 Line by line
If that Preceptor can call the Dragon Kings to show themselves, then let the credit be reckoned his.”
那國師: 那 = nà. 叫得龍王現身: 得 = de, marking whether he can manage it at all. 功勞 "merit, credit." The terms sound scrupulously fair, and they are: whoever can do it, wins.
The king said in great delight, “In the twenty-three years I have been emperor, I have never once seen what a live dragon looks like.
更不曾: 更 = gèng. 看見: 看 = kàn. 做了: 了 = le. 活龍 "a living dragon." Twenty-three years on the throne of a kingdom whose whole religious establishment claims to command dragons, and he has never seen one. Nobody in the room remarks on this.
Let your two parties each display your powers — monk or Daoist, no matter — whoever can call them here has the merit;
兩家各顯法力 "let each side show its power." 不論僧道: the falling tone of 論 pulls 不 to bú -- "monk or Daoist, it makes no difference." 叫得來: 得 = de.
whoever cannot call them out is guilty.”
叫不出: the level tone of 出 keeps 不 at bù. 有罪 "is at fault."
The test is perfectly chosen. A dragon cannot be produced by burning paper, and it cannot be argued into the sky. Either one appears or it does not.
The king seizes on it with the delight of a child at a fair -- twenty-three years as emperor and he has never seen a live one. That line does a lot of quiet work. His Preceptors have been commanding dragons on his behalf for years and have never once shown him the goods.
And the terms are impeccably even: monk or Daoist, whoever can call them has the credit, whoever cannot is guilty. It looks like scrupulous fairness. It is a challenge that is impossible for one side and trivial for the other, and Wukong wrote it.