我解得，我解得 I Understand It, I Understand It
三藏道：「《般若心經》是我隨身衣缽，自那烏巢禪師教後，那一日不念？那一時得忘？顛倒也念得來，怎會忘得？」行者道：「師父只是念得，不曾求那師父解得。」三藏說：「猴頭，怎又說我不曾解得？你解得麼？」行者道：「我解得，我解得。」自此，三藏、行者再不作聲。旁邊笑倒一個八戒，喜壞一個沙僧，說道：「嘴巴，替我一般的做妖精出身，又不是那裡禪和子聽過講經，那裡應佛僧也曾見過說法。三藏道：「《般若心经》是我随身衣钵，自那乌巢禅师教后，那一日不念？那一时得忘？颠倒也念得来，怎会忘得？」行者道：「师父只是念得，不曾求那师父解得。」三藏说：「猴头，怎又说我不曾解得？你解得么？」行者道：「我解得，我解得。」自此，三藏、行者再不作声。旁边笑倒一个八戒，喜坏一个沙僧，说道：「嘴巴，替我一般的做妖精出身，又不是那里禅和子听过讲经，那里应佛僧也曾见过说法。
逐句解 Line by line
Tripitaka said, "The Prajna Heart Scripture is the robe and bowl I carry on my body. Since the Crow's Nest Chan Master taught it to me, which day have I not recited it? Which hour could I forget it? I can say it backwards. How should I forget it?"
衣缽 — robe and bowl — are the only two things a monk properly owns, and the phrase came to mean whatever is handed down from master to pupil. Tripitaka is saying the scripture is not something he has, it is something he is.
Both 那 here are questions, not the everyday "that" — nǎ rather than nà. Which day, which hour. The chapter uses the same character both ways more than fifty times, and this pair sits well away from the usual place a question mark turns up, which is exactly why they are easy to miss.
顛倒也念得來 — he can recite it upside down. It is a boast, and the novel is about to take it apart.
Pilgrim said, "Master, you can only recite it. You never asked that master to explain it." Tripitaka said, "Ape's head! How can you say I do not understand it? Do you understand it?" Pilgrim said, "I understand it. I understand it."
The whole argument turns on one character. 念得 is reciting; 解得 is understanding. Tripitaka has the first and assumes the second follows.
猴頭 — ape's head — is what Tripitaka calls Pilgrim when he is losing his temper, and it lands harder here because he is losing an argument as well.
Pilgrim says he understands it twice. Repeating a claim instead of proving it is usually how this novel marks a boast — but this once, he means it, and the proof is what he does next.
From this point, Tripitaka and Pilgrim did not make another sound. Off to one side, Eight Rules fell about laughing and Sha Monk was tickled half to death, and he said, "Big mouth! You came out of a demon's hide the same as I did. It is not as though you were some Chan monk from somewhere who has sat through the scriptures being expounded, or one of those chanting monks who has watched the Law being preached."
This is the hinge of the argument and it is easy to read past. Neither of them says anything more — and the silence is the answer. Pilgrim has just shown a wordless understanding by shutting up, and Tripitaka has understood him by shutting up too.
應佛僧 are the jobbing monks hired to chant at funerals and memorial services — the trade end of the profession. Eight Rules is sneering that Pilgrim has had no training of any kind, not even the cheap kind.
Note that Eight Rules says 替我一般的做妖精出身 — you started out a demon the same as me. It is true of both of them, and of Sha Monk, and it is the reason all three are on this road.
This is one of the most-quoted exchanges in the later chapters, and it is over in four lines. Tripitaka can recite the Heart Scripture backwards. Pilgrim points out that reciting is not understanding. Tripitaka demands to know whether the monkey understands it. The monkey says he does, twice, and then neither of them speaks again.
That silence is the argument. The Heart Scripture is the text that says form is emptiness and emptiness is form, and that there is nothing to attain; a commentary on it that used a lot of words would be missing its own point. So Pilgrim answers with none, and Tripitaka's own silence is his concession. When he finally speaks, a few lines further on, it is to say so out loud.
The comedy underneath is that neither Eight Rules nor Sha Monk can see any of this happening. To them the conversation simply stopped, and they assume their big brother has been caught bluffing. Eight Rules jeers that Pilgrim has never sat through a lecture in his life — which is entirely true, and entirely beside the point.