三折之肱 The Thrice Broken Arm
我師父是唐王御弟唐三藏。我是他大徒弟孫悟空。因過你國倒換關文，見你君臣出榜招醫，是我大施三折之肱，把他相思之病治好了，排宴謝我。我师父是唐王御弟唐三藏。我是他大徒弟孙悟空。因过你国倒换关文，见你君臣出榜招医，是我大施三折之肱，把他相思之病治好了，排宴谢我。
逐句解 Line by line
"My master is the Tang emperor's sworn younger brother, Tang Sanzang.
藏 is zàng in the monk's name. 御弟 is the title an emperor confers on a sworn younger brother — so the master is introduced by his relation to a throne, and in the next sentence the disciple is introduced by his relation to the master.
"I am his eldest disciple, Sun Wukong.
Nine characters, and the name arrives third in the sequence — errand, then master, then himself. He gave it to the demon's vanguard in the first line of the chapter and has not used it since.
"Passing through your kingdom to have our travel papers stamped, I saw that your sovereign and his ministers had put out a notice calling for a physician. I brought out the skill of the thrice-broken arm and cured him of his sickness of longing, and he laid on a banquet to thank me.
倒 is dǎo inside 倒換, to exchange one thing for another — getting travel papers stamped. 三折之肱 comes from the proverb that a man who has broken his own arm three times knows how to set one, so the claim is to hard experience rather than to gift. And 相思之病 names the king's illness for the first and only time in the chapter: the sickness of longing.
Thirty-seven characters of biography, and the chapter has been withholding all of it. We have known since the second block that the king was ill and that Wukong arrived as a physician; we have not until now been told what the illness was. It was longing — and the man who cured it is explaining that to the woman he was longing for.
The proverb he reaches for is a modest one. Not that he is gifted but that he has broken his own arm three times, so the skill is presented as the residue of accidents. It is the only claim in the whole speech that is not about power.