原文 Original text
繁體 Traditional
Reader's edition
他醜自醜 Ugly but All of Them Useful
三藏道：「他醜自醜，卻俱有用。你快請他進來，若再遲了些兒，那雷公嘴的有些闖禍，不是個人生父母養的，他就打進來也。」三藏道：「他丑自丑，却俱有用。你快请他进来，若再迟了些儿，那雷公嘴的有些闯祸，不是个人生父母养的，他就打进来也。」
逐句解 Line by line
三藏道：「他醜自醜，卻俱有用。
三藏道：「他丑自丑，却俱有用。
Tripitaka said, "Ugly they may be, but they are all of them useful.
他醜自醜 — let them be ugly, they are ugly; the doubled construction concedes the point and dismisses it in four characters.
你快請他進來，若再遲了些兒，那雷公嘴的有些闖禍，不是個人生父母養的，他就打進來也。」
你快请他进来，若再迟了些儿，那雷公嘴的有些闯祸，不是个人生父母养的，他就打进来也。」
Ask them in quickly. If you delay a moment longer, the one with the thunder-god's beak has a way of making trouble. He was not born of any human parents, and he will come in by force."
不是個人生父母養的 is literally "not one born of human parents and raised by them" — perfectly true of a monkey hatched from a stone, and used here as a warning rather than an insult.
The defence is affectionate and entirely accurate. They are ugly, they are useful, and if you keep the first one waiting he will knock the gate down.
It is also the closest thing to an apology Pilgrim gets in this chapter. His master overruled him, dismissed his evidence, told him to sit down, and now describes him to a stranger as somebody who was never human and is not to be kept waiting. Coming from Tripitaka, that is affection.